Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

29 files changed, 13081 insertions, 0 deletions

diff --git a/src/tools/rust-analyzer/crates/syntax/src/algo.rs b/src/tools/rust-analyzer/crates/syntax/src/algo.rs
new file mode 100644
index 000000000..8b14789dd
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/algo.rs
@@ -0,0 +1,660 @@
+//! Collection of assorted algorithms for syntax trees.
+
+use std::hash::BuildHasherDefault;
+
+use indexmap::IndexMap;
+use itertools::Itertools;
+use rustc_hash::FxHashMap;
+use text_edit::TextEditBuilder;
+
+use crate::{
+    AstNode, Direction, NodeOrToken, SyntaxElement, SyntaxKind, SyntaxNode, SyntaxToken, TextRange,
+    TextSize,
+};
+
+/// Returns ancestors of the node at the offset, sorted by length. This should
+/// do the right thing at an edge, e.g. when searching for expressions at `{
+/// $0foo }` we will get the name reference instead of the whole block, which
+/// we would get if we just did `find_token_at_offset(...).flat_map(|t|
+/// t.parent().ancestors())`.
+pub fn ancestors_at_offset(
+    node: &SyntaxNode,
+    offset: TextSize,
+) -> impl Iterator<Item = SyntaxNode> {
+    node.token_at_offset(offset)
+        .map(|token| token.parent_ancestors())
+        .kmerge_by(|node1, node2| node1.text_range().len() < node2.text_range().len())
+}
+
+/// Finds a node of specific Ast type at offset. Note that this is slightly
+/// imprecise: if the cursor is strictly between two nodes of the desired type,
+/// as in
+///
+/// ```no_run
+/// struct Foo {}|struct Bar;
+/// ```
+///
+/// then the shorter node will be silently preferred.
+pub fn find_node_at_offset<N: AstNode>(syntax: &SyntaxNode, offset: TextSize) -> Option<N> {
+    ancestors_at_offset(syntax, offset).find_map(N::cast)
+}
+
+pub fn find_node_at_range<N: AstNode>(syntax: &SyntaxNode, range: TextRange) -> Option<N> {
+    syntax.covering_element(range).ancestors().find_map(N::cast)
+}
+
+/// Skip to next non `trivia` token
+pub fn skip_trivia_token(mut token: SyntaxToken, direction: Direction) -> Option<SyntaxToken> {
+    while token.kind().is_trivia() {
+        token = match direction {
+            Direction::Next => token.next_token()?,
+            Direction::Prev => token.prev_token()?,
+        }
+    }
+    Some(token)
+}
+/// Skip to next non `whitespace` token
+pub fn skip_whitespace_token(mut token: SyntaxToken, direction: Direction) -> Option<SyntaxToken> {
+    while token.kind() == SyntaxKind::WHITESPACE {
+        token = match direction {
+            Direction::Next => token.next_token()?,
+            Direction::Prev => token.prev_token()?,
+        }
+    }
+    Some(token)
+}
+
+/// Finds the first sibling in the given direction which is not `trivia`
+pub fn non_trivia_sibling(element: SyntaxElement, direction: Direction) -> Option<SyntaxElement> {
+    return match element {
+        NodeOrToken::Node(node) => node.siblings_with_tokens(direction).skip(1).find(not_trivia),
+        NodeOrToken::Token(token) => token.siblings_with_tokens(direction).skip(1).find(not_trivia),
+    };
+
+    fn not_trivia(element: &SyntaxElement) -> bool {
+        match element {
+            NodeOrToken::Node(_) => true,
+            NodeOrToken::Token(token) => !token.kind().is_trivia(),
+        }
+    }
+}
+
+pub fn least_common_ancestor(u: &SyntaxNode, v: &SyntaxNode) -> Option<SyntaxNode> {
+    if u == v {
+        return Some(u.clone());
+    }
+
+    let u_depth = u.ancestors().count();
+    let v_depth = v.ancestors().count();
+    let keep = u_depth.min(v_depth);
+
+    let u_candidates = u.ancestors().skip(u_depth - keep);
+    let v_candidates = v.ancestors().skip(v_depth - keep);
+    let (res, _) = u_candidates.zip(v_candidates).find(|(x, y)| x == y)?;
+    Some(res)
+}
+
+pub fn neighbor<T: AstNode>(me: &T, direction: Direction) -> Option<T> {
+    me.syntax().siblings(direction).skip(1).find_map(T::cast)
+}
+
+pub fn has_errors(node: &SyntaxNode) -> bool {
+    node.children().any(|it| it.kind() == SyntaxKind::ERROR)
+}
+
+type FxIndexMap<K, V> = IndexMap<K, V, BuildHasherDefault<rustc_hash::FxHasher>>;
+
+#[derive(Debug, Hash, PartialEq, Eq)]
+enum TreeDiffInsertPos {
+    After(SyntaxElement),
+    AsFirstChild(SyntaxElement),
+}
+
+#[derive(Debug)]
+pub struct TreeDiff {
+    replacements: FxHashMap<SyntaxElement, SyntaxElement>,
+    deletions: Vec<SyntaxElement>,
+    // the vec as well as the indexmap are both here to preserve order
+    insertions: FxIndexMap<TreeDiffInsertPos, Vec<SyntaxElement>>,
+}
+
+impl TreeDiff {
+    pub fn into_text_edit(&self, builder: &mut TextEditBuilder) {
+        let _p = profile::span("into_text_edit");
+
+        for (anchor, to) in &self.insertions {
+            let offset = match anchor {
+                TreeDiffInsertPos::After(it) => it.text_range().end(),
+                TreeDiffInsertPos::AsFirstChild(it) => it.text_range().start(),
+            };
+            to.iter().for_each(|to| builder.insert(offset, to.to_string()));
+        }
+        for (from, to) in &self.replacements {
+            builder.replace(from.text_range(), to.to_string());
+        }
+        for text_range in self.deletions.iter().map(SyntaxElement::text_range) {
+            builder.delete(text_range);
+        }
+    }
+
+    pub fn is_empty(&self) -> bool {
+        self.replacements.is_empty() && self.deletions.is_empty() && self.insertions.is_empty()
+    }
+}
+
+/// Finds a (potentially minimal) diff, which, applied to `from`, will result in `to`.
+///
+/// Specifically, returns a structure that consists of a replacements, insertions and deletions
+/// such that applying this map on `from` will result in `to`.
+///
+/// This function tries to find a fine-grained diff.
+pub fn diff(from: &SyntaxNode, to: &SyntaxNode) -> TreeDiff {
+    let _p = profile::span("diff");
+
+    let mut diff = TreeDiff {
+        replacements: FxHashMap::default(),
+        insertions: FxIndexMap::default(),
+        deletions: Vec::new(),
+    };
+    let (from, to) = (from.clone().into(), to.clone().into());
+
+    if !syntax_element_eq(&from, &to) {
+        go(&mut diff, from, to);
+    }
+    return diff;
+
+    fn syntax_element_eq(lhs: &SyntaxElement, rhs: &SyntaxElement) -> bool {
+        lhs.kind() == rhs.kind()
+            && lhs.text_range().len() == rhs.text_range().len()
+            && match (&lhs, &rhs) {
+                (NodeOrToken::Node(lhs), NodeOrToken::Node(rhs)) => {
+                    lhs == rhs || lhs.text() == rhs.text()
+                }
+                (NodeOrToken::Token(lhs), NodeOrToken::Token(rhs)) => lhs.text() == rhs.text(),
+                _ => false,
+            }
+    }
+
+    // FIXME: this is horribly inefficient. I bet there's a cool algorithm to diff trees properly.
+    fn go(diff: &mut TreeDiff, lhs: SyntaxElement, rhs: SyntaxElement) {
+        let (lhs, rhs) = match lhs.as_node().zip(rhs.as_node()) {
+            Some((lhs, rhs)) => (lhs, rhs),
+            _ => {
+                cov_mark::hit!(diff_node_token_replace);
+                diff.replacements.insert(lhs, rhs);
+                return;
+            }
+        };
+
+        let mut look_ahead_scratch = Vec::default();
+
+        let mut rhs_children = rhs.children_with_tokens();
+        let mut lhs_children = lhs.children_with_tokens();
+        let mut last_lhs = None;
+        loop {
+            let lhs_child = lhs_children.next();
+            match (lhs_child.clone(), rhs_children.next()) {
+                (None, None) => break,
+                (None, Some(element)) => {
+                    let insert_pos = match last_lhs.clone() {
+                        Some(prev) => {
+                            cov_mark::hit!(diff_insert);
+                            TreeDiffInsertPos::After(prev)
+                        }
+                        // first iteration, insert into out parent as the first child
+                        None => {
+                            cov_mark::hit!(diff_insert_as_first_child);
+                            TreeDiffInsertPos::AsFirstChild(lhs.clone().into())
+                        }
+                    };
+                    diff.insertions.entry(insert_pos).or_insert_with(Vec::new).push(element);
+                }
+                (Some(element), None) => {
+                    cov_mark::hit!(diff_delete);
+                    diff.deletions.push(element);
+                }
+                (Some(ref lhs_ele), Some(ref rhs_ele)) if syntax_element_eq(lhs_ele, rhs_ele) => {}
+                (Some(lhs_ele), Some(rhs_ele)) => {
+                    // nodes differ, look for lhs_ele in rhs, if its found we can mark everything up
+                    // until that element as insertions. This is important to keep the diff minimal
+                    // in regards to insertions that have been actually done, this is important for
+                    // use insertions as we do not want to replace the entire module node.
+                    look_ahead_scratch.push(rhs_ele.clone());
+                    let mut rhs_children_clone = rhs_children.clone();
+                    let mut insert = false;
+                    for rhs_child in &mut rhs_children_clone {
+                        if syntax_element_eq(&lhs_ele, &rhs_child) {
+                            cov_mark::hit!(diff_insertions);
+                            insert = true;
+                            break;
+                        }
+                        look_ahead_scratch.push(rhs_child);
+                    }
+                    let drain = look_ahead_scratch.drain(..);
+                    if insert {
+                        let insert_pos = if let Some(prev) = last_lhs.clone().filter(|_| insert) {
+                            TreeDiffInsertPos::After(prev)
+                        } else {
+                            cov_mark::hit!(insert_first_child);
+                            TreeDiffInsertPos::AsFirstChild(lhs.clone().into())
+                        };
+
+                        diff.insertions.entry(insert_pos).or_insert_with(Vec::new).extend(drain);
+                        rhs_children = rhs_children_clone;
+                    } else {
+                        go(diff, lhs_ele, rhs_ele);
+                    }
+                }
+            }
+            last_lhs = lhs_child.or(last_lhs);
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use expect_test::{expect, Expect};
+    use itertools::Itertools;
+    use parser::SyntaxKind;
+    use text_edit::TextEdit;
+
+    use crate::{AstNode, SyntaxElement};
+
+    #[test]
+    fn replace_node_token() {
+        cov_mark::check!(diff_node_token_replace);
+        check_diff(
+            r#"use node;"#,
+            r#"ident"#,
+            expect![[r#"
+                insertions:
+
+
+
+                replacements:
+
+                Line 0: Token(USE_KW@0..3 "use") -> ident
+
+                deletions:
+
+                Line 1: " "
+                Line 1: node
+                Line 1: ;
+            "#]],
+        );
+    }
+
+    #[test]
+    fn replace_parent() {
+        cov_mark::check!(diff_insert_as_first_child);
+        check_diff(
+            r#""#,
+            r#"use foo::bar;"#,
+            expect![[r#"
+                insertions:
+
+                Line 0: AsFirstChild(Node(SOURCE_FILE@0..0))
+                -> use foo::bar;
+
+                replacements:
+
+
+
+                deletions:
+
+
+            "#]],
+        );
+    }
+
+    #[test]
+    fn insert_last() {
+        cov_mark::check!(diff_insert);
+        check_diff(
+            r#"
+use foo;
+use bar;"#,
+            r#"
+use foo;
+use bar;
+use baz;"#,
+            expect![[r#"
+                insertions:
+
+                Line 2: After(Node(USE@10..18))
+                -> "\n"
+                -> use baz;
+
+                replacements:
+
+
+
+                deletions:
+
+
+            "#]],
+        );
+    }
+
+    #[test]
+    fn insert_middle() {
+        check_diff(
+            r#"
+use foo;
+use baz;"#,
+            r#"
+use foo;
+use bar;
+use baz;"#,
+            expect![[r#"
+                insertions:
+
+                Line 2: After(Token(WHITESPACE@9..10 "\n"))
+                -> use bar;
+                -> "\n"
+
+                replacements:
+
+
+
+                deletions:
+
+
+            "#]],
+        )
+    }
+
+    #[test]
+    fn insert_first() {
+        check_diff(
+            r#"
+use bar;
+use baz;"#,
+            r#"
+use foo;
+use bar;
+use baz;"#,
+            expect![[r#"
+                insertions:
+
+                Line 0: After(Token(WHITESPACE@0..1 "\n"))
+                -> use foo;
+                -> "\n"
+
+                replacements:
+
+
+
+                deletions:
+
+
+            "#]],
+        )
+    }
+
+    #[test]
+    fn first_child_insertion() {
+        cov_mark::check!(insert_first_child);
+        check_diff(
+            r#"fn main() {
+        stdi
+    }"#,
+            r#"use foo::bar;
+
+    fn main() {
+        stdi
+    }"#,
+            expect![[r#"
+                insertions:
+
+                Line 0: AsFirstChild(Node(SOURCE_FILE@0..30))
+                -> use foo::bar;
+                -> "\n\n    "
+
+                replacements:
+
+
+
+                deletions:
+
+
+            "#]],
+        );
+    }
+
+    #[test]
+    fn delete_last() {
+        cov_mark::check!(diff_delete);
+        check_diff(
+            r#"use foo;
+            use bar;"#,
+            r#"use foo;"#,
+            expect![[r#"
+                insertions:
+
+
+
+                replacements:
+
+
+
+                deletions:
+
+                Line 1: "\n            "
+                Line 2: use bar;
+            "#]],
+        );
+    }
+
+    #[test]
+    fn delete_middle() {
+        cov_mark::check!(diff_insertions);
+        check_diff(
+            r#"
+use expect_test::{expect, Expect};
+use text_edit::TextEdit;
+
+use crate::AstNode;
+"#,
+            r#"
+use expect_test::{expect, Expect};
+
+use crate::AstNode;
+"#,
+            expect![[r#"
+                insertions:
+
+                Line 1: After(Node(USE@1..35))
+                -> "\n\n"
+                -> use crate::AstNode;
+
+                replacements:
+
+
+
+                deletions:
+
+                Line 2: use text_edit::TextEdit;
+                Line 3: "\n\n"
+                Line 4: use crate::AstNode;
+                Line 5: "\n"
+            "#]],
+        )
+    }
+
+    #[test]
+    fn delete_first() {
+        check_diff(
+            r#"
+use text_edit::TextEdit;
+
+use crate::AstNode;
+"#,
+            r#"
+use crate::AstNode;
+"#,
+            expect![[r#"
+                insertions:
+
+
+
+                replacements:
+
+                Line 2: Token(IDENT@5..14 "text_edit") -> crate
+                Line 2: Token(IDENT@16..24 "TextEdit") -> AstNode
+                Line 2: Token(WHITESPACE@25..27 "\n\n") -> "\n"
+
+                deletions:
+
+                Line 3: use crate::AstNode;
+                Line 4: "\n"
+            "#]],
+        )
+    }
+
+    #[test]
+    fn merge_use() {
+        check_diff(
+            r#"
+use std::{
+    fmt,
+    hash::BuildHasherDefault,
+    ops::{self, RangeInclusive},
+};
+"#,
+            r#"
+use std::fmt;
+use std::hash::BuildHasherDefault;
+use std::ops::{self, RangeInclusive};
+"#,
+            expect![[r#"
+                insertions:
+
+                Line 2: After(Node(PATH_SEGMENT@5..8))
+                -> ::
+                -> fmt
+                Line 6: After(Token(WHITESPACE@86..87 "\n"))
+                -> use std::hash::BuildHasherDefault;
+                -> "\n"
+                -> use std::ops::{self, RangeInclusive};
+                -> "\n"
+
+                replacements:
+
+                Line 2: Token(IDENT@5..8 "std") -> std
+
+                deletions:
+
+                Line 2: ::
+                Line 2: {
+                    fmt,
+                    hash::BuildHasherDefault,
+                    ops::{self, RangeInclusive},
+                }
+            "#]],
+        )
+    }
+
+    #[test]
+    fn early_return_assist() {
+        check_diff(
+            r#"
+fn main() {
+    if let Ok(x) = Err(92) {
+        foo(x);
+    }
+}
+            "#,
+            r#"
+fn main() {
+    let x = match Err(92) {
+        Ok(it) => it,
+        _ => return,
+    };
+    foo(x);
+}
+            "#,
+            expect![[r#"
+                insertions:
+
+                Line 3: After(Node(BLOCK_EXPR@40..63))
+                -> " "
+                -> match Err(92) {
+                        Ok(it) => it,
+                        _ => return,
+                    }
+                -> ;
+                Line 3: After(Node(IF_EXPR@17..63))
+                -> "\n    "
+                -> foo(x);
+
+                replacements:
+
+                Line 3: Token(IF_KW@17..19 "if") -> let
+                Line 3: Token(LET_KW@20..23 "let") -> x
+                Line 3: Node(BLOCK_EXPR@40..63) -> =
+
+                deletions:
+
+                Line 3: " "
+                Line 3: Ok(x)
+                Line 3: " "
+                Line 3: =
+                Line 3: " "
+                Line 3: Err(92)
+            "#]],
+        )
+    }
+
+    fn check_diff(from: &str, to: &str, expected_diff: Expect) {
+        let from_node = crate::SourceFile::parse(from).tree().syntax().clone();
+        let to_node = crate::SourceFile::parse(to).tree().syntax().clone();
+        let diff = super::diff(&from_node, &to_node);
+
+        let line_number =
+            |syn: &SyntaxElement| from[..syn.text_range().start().into()].lines().count();
+
+        let fmt_syntax = |syn: &SyntaxElement| match syn.kind() {
+            SyntaxKind::WHITESPACE => format!("{:?}", syn.to_string()),
+            _ => format!("{}", syn),
+        };
+
+        let insertions =
+            diff.insertions.iter().format_with("\n", |(k, v), f| -> Result<(), std::fmt::Error> {
+                f(&format!(
+                    "Line {}: {:?}\n-> {}",
+                    line_number(match k {
+                        super::TreeDiffInsertPos::After(syn) => syn,
+                        super::TreeDiffInsertPos::AsFirstChild(syn) => syn,
+                    }),
+                    k,
+                    v.iter().format_with("\n-> ", |v, f| f(&fmt_syntax(v)))
+                ))
+            });
+
+        let replacements = diff
+            .replacements
+            .iter()
+            .sorted_by_key(|(syntax, _)| syntax.text_range().start())
+            .format_with("\n", |(k, v), f| {
+                f(&format!("Line {}: {:?} -> {}", line_number(k), k, fmt_syntax(v)))
+            });
+
+        let deletions = diff
+            .deletions
+            .iter()
+            .format_with("\n", |v, f| f(&format!("Line {}: {}", line_number(v), &fmt_syntax(v))));
+
+        let actual = format!(
+            "insertions:\n\n{}\n\nreplacements:\n\n{}\n\ndeletions:\n\n{}\n",
+            insertions, replacements, deletions
+        );
+        expected_diff.assert_eq(&actual);
+
+        let mut from = from.to_owned();
+        let mut text_edit = TextEdit::builder();
+        diff.into_text_edit(&mut text_edit);
+        text_edit.finish().apply(&mut from);
+        assert_eq!(&*from, to, "diff did not turn `from` to `to`");
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ast.rs b/src/tools/rust-analyzer/crates/syntax/src/ast.rs
new file mode 100644
index 000000000..4aa64d0d6
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/ast.rs
@@ -0,0 +1,367 @@
+//! Abstract Syntax Tree, layered on top of untyped `SyntaxNode`s
+
+mod generated;
+mod traits;
+mod token_ext;
+mod node_ext;
+mod expr_ext;
+mod operators;
+pub mod edit;
+pub mod edit_in_place;
+pub mod make;
+
+use std::marker::PhantomData;
+
+use crate::{
+    syntax_node::{SyntaxNode, SyntaxNodeChildren, SyntaxToken},
+    SyntaxKind,
+};
+
+pub use self::{
+    expr_ext::{ArrayExprKind, BlockModifier, CallableExpr, ElseBranch, LiteralKind},
+    generated::{nodes::*, tokens::*},
+    node_ext::{
+        AttrKind, FieldKind, Macro, NameLike, NameOrNameRef, PathSegmentKind, SelfParamKind,
+        SlicePatComponents, StructKind, TypeBoundKind, TypeOrConstParam, VisibilityKind,
+    },
+    operators::{ArithOp, BinaryOp, CmpOp, LogicOp, Ordering, RangeOp, UnaryOp},
+    token_ext::{CommentKind, CommentPlacement, CommentShape, IsString, QuoteOffsets, Radix},
+    traits::{
+        AttrDocCommentIter, DocCommentIter, HasArgList, HasAttrs, HasDocComments, HasGenericParams,
+        HasLoopBody, HasModuleItem, HasName, HasTypeBounds, HasVisibility,
+    },
+};
+
+/// The main trait to go from untyped `SyntaxNode`  to a typed ast. The
+/// conversion itself has zero runtime cost: ast and syntax nodes have exactly
+/// the same representation: a pointer to the tree root and a pointer to the
+/// node itself.
+pub trait AstNode {
+    fn can_cast(kind: SyntaxKind) -> bool
+    where
+        Self: Sized;
+
+    fn cast(syntax: SyntaxNode) -> Option<Self>
+    where
+        Self: Sized;
+
+    fn syntax(&self) -> &SyntaxNode;
+    fn clone_for_update(&self) -> Self
+    where
+        Self: Sized,
+    {
+        Self::cast(self.syntax().clone_for_update()).unwrap()
+    }
+    fn clone_subtree(&self) -> Self
+    where
+        Self: Sized,
+    {
+        Self::cast(self.syntax().clone_subtree()).unwrap()
+    }
+}
+
+/// Like `AstNode`, but wraps tokens rather than interior nodes.
+pub trait AstToken {
+    fn can_cast(token: SyntaxKind) -> bool
+    where
+        Self: Sized;
+
+    fn cast(syntax: SyntaxToken) -> Option<Self>
+    where
+        Self: Sized;
+
+    fn syntax(&self) -> &SyntaxToken;
+
+    fn text(&self) -> &str {
+        self.syntax().text()
+    }
+}
+
+/// An iterator over `SyntaxNode` children of a particular AST type.
+#[derive(Debug, Clone)]
+pub struct AstChildren<N> {
+    inner: SyntaxNodeChildren,
+    ph: PhantomData<N>,
+}
+
+impl<N> AstChildren<N> {
+    fn new(parent: &SyntaxNode) -> Self {
+        AstChildren { inner: parent.children(), ph: PhantomData }
+    }
+}
+
+impl<N: AstNode> Iterator for AstChildren<N> {
+    type Item = N;
+    fn next(&mut self) -> Option<N> {
+        self.inner.find_map(N::cast)
+    }
+}
+
+mod support {
+    use super::{AstChildren, AstNode, SyntaxKind, SyntaxNode, SyntaxToken};
+
+    pub(super) fn child<N: AstNode>(parent: &SyntaxNode) -> Option<N> {
+        parent.children().find_map(N::cast)
+    }
+
+    pub(super) fn children<N: AstNode>(parent: &SyntaxNode) -> AstChildren<N> {
+        AstChildren::new(parent)
+    }
+
+    pub(super) fn token(parent: &SyntaxNode, kind: SyntaxKind) -> Option<SyntaxToken> {
+        parent.children_with_tokens().filter_map(|it| it.into_token()).find(|it| it.kind() == kind)
+    }
+}
+
+#[test]
+fn assert_ast_is_object_safe() {
+    fn _f(_: &dyn AstNode, _: &dyn HasName) {}
+}
+
+#[test]
+fn test_doc_comment_none() {
+    let file = SourceFile::parse(
+        r#"
+        // non-doc
+        mod foo {}
+        "#,
+    )
+    .ok()
+    .unwrap();
+    let module = file.syntax().descendants().find_map(Module::cast).unwrap();
+    assert!(module.doc_comments().doc_comment_text().is_none());
+}
+
+#[test]
+fn test_outer_doc_comment_of_items() {
+    let file = SourceFile::parse(
+        r#"
+        /// doc
+        // non-doc
+        mod foo {}
+        "#,
+    )
+    .ok()
+    .unwrap();
+    let module = file.syntax().descendants().find_map(Module::cast).unwrap();
+    assert_eq!(" doc", module.doc_comments().doc_comment_text().unwrap());
+}
+
+#[test]
+fn test_inner_doc_comment_of_items() {
+    let file = SourceFile::parse(
+        r#"
+        //! doc
+        // non-doc
+        mod foo {}
+        "#,
+    )
+    .ok()
+    .unwrap();
+    let module = file.syntax().descendants().find_map(Module::cast).unwrap();
+    assert!(module.doc_comments().doc_comment_text().is_none());
+}
+
+#[test]
+fn test_doc_comment_of_statics() {
+    let file = SourceFile::parse(
+        r#"
+        /// Number of levels
+        static LEVELS: i32 = 0;
+        "#,
+    )
+    .ok()
+    .unwrap();
+    let st = file.syntax().descendants().find_map(Static::cast).unwrap();
+    assert_eq!(" Number of levels", st.doc_comments().doc_comment_text().unwrap());
+}
+
+#[test]
+fn test_doc_comment_preserves_indents() {
+    let file = SourceFile::parse(
+        r#"
+        /// doc1
+        /// ```
+        /// fn foo() {
+        ///     // ...
+        /// }
+        /// ```
+        mod foo {}
+        "#,
+    )
+    .ok()
+    .unwrap();
+    let module = file.syntax().descendants().find_map(Module::cast).unwrap();
+    assert_eq!(
+        " doc1\n ```\n fn foo() {\n     // ...\n }\n ```",
+        module.doc_comments().doc_comment_text().unwrap()
+    );
+}
+
+#[test]
+fn test_doc_comment_preserves_newlines() {
+    let file = SourceFile::parse(
+        r#"
+        /// this
+        /// is
+        /// mod
+        /// foo
+        mod foo {}
+        "#,
+    )
+    .ok()
+    .unwrap();
+    let module = file.syntax().descendants().find_map(Module::cast).unwrap();
+    assert_eq!(" this\n is\n mod\n foo", module.doc_comments().doc_comment_text().unwrap());
+}
+
+#[test]
+fn test_doc_comment_single_line_block_strips_suffix() {
+    let file = SourceFile::parse(
+        r#"
+        /** this is mod foo*/
+        mod foo {}
+        "#,
+    )
+    .ok()
+    .unwrap();
+    let module = file.syntax().descendants().find_map(Module::cast).unwrap();
+    assert_eq!(" this is mod foo", module.doc_comments().doc_comment_text().unwrap());
+}
+
+#[test]
+fn test_doc_comment_single_line_block_strips_suffix_whitespace() {
+    let file = SourceFile::parse(
+        r#"
+        /** this is mod foo */
+        mod foo {}
+        "#,
+    )
+    .ok()
+    .unwrap();
+    let module = file.syntax().descendants().find_map(Module::cast).unwrap();
+    assert_eq!(" this is mod foo ", module.doc_comments().doc_comment_text().unwrap());
+}
+
+#[test]
+fn test_doc_comment_multi_line_block_strips_suffix() {
+    let file = SourceFile::parse(
+        r#"
+        /**
+        this
+        is
+        mod foo
+        */
+        mod foo {}
+        "#,
+    )
+    .ok()
+    .unwrap();
+    let module = file.syntax().descendants().find_map(Module::cast).unwrap();
+    assert_eq!(
+        "\n        this\n        is\n        mod foo\n        ",
+        module.doc_comments().doc_comment_text().unwrap()
+    );
+}
+
+#[test]
+fn test_comments_preserve_trailing_whitespace() {
+    let file = SourceFile::parse(
+        "\n/// Representation of a Realm.   \n/// In the specification these are called Realm Records.\nstruct Realm {}",
+    )
+    .ok()
+    .unwrap();
+    let def = file.syntax().descendants().find_map(Struct::cast).unwrap();
+    assert_eq!(
+        " Representation of a Realm.   \n In the specification these are called Realm Records.",
+        def.doc_comments().doc_comment_text().unwrap()
+    );
+}
+
+#[test]
+fn test_four_slash_line_comment() {
+    let file = SourceFile::parse(
+        r#"
+        //// too many slashes to be a doc comment
+        /// doc comment
+        mod foo {}
+        "#,
+    )
+    .ok()
+    .unwrap();
+    let module = file.syntax().descendants().find_map(Module::cast).unwrap();
+    assert_eq!(" doc comment", module.doc_comments().doc_comment_text().unwrap());
+}
+
+#[test]
+fn test_where_predicates() {
+    fn assert_bound(text: &str, bound: Option<TypeBound>) {
+        assert_eq!(text, bound.unwrap().syntax().text().to_string());
+    }
+
+    let file = SourceFile::parse(
+        r#"
+fn foo()
+where
+   T: Clone + Copy + Debug + 'static,
+   'a: 'b + 'c,
+   Iterator::Item: 'a + Debug,
+   Iterator::Item: Debug + 'a,
+   <T as Iterator>::Item: Debug + 'a,
+   for<'a> F: Fn(&'a str)
+{}
+        "#,
+    )
+    .ok()
+    .unwrap();
+    let where_clause = file.syntax().descendants().find_map(WhereClause::cast).unwrap();
+
+    let mut predicates = where_clause.predicates();
+
+    let pred = predicates.next().unwrap();
+    let mut bounds = pred.type_bound_list().unwrap().bounds();
+
+    assert!(pred.for_token().is_none());
+    assert!(pred.generic_param_list().is_none());
+    assert_eq!("T", pred.ty().unwrap().syntax().text().to_string());
+    assert_bound("Clone", bounds.next());
+    assert_bound("Copy", bounds.next());
+    assert_bound("Debug", bounds.next());
+    assert_bound("'static", bounds.next());
+
+    let pred = predicates.next().unwrap();
+    let mut bounds = pred.type_bound_list().unwrap().bounds();
+
+    assert_eq!("'a", pred.lifetime().unwrap().lifetime_ident_token().unwrap().text());
+
+    assert_bound("'b", bounds.next());
+    assert_bound("'c", bounds.next());
+
+    let pred = predicates.next().unwrap();
+    let mut bounds = pred.type_bound_list().unwrap().bounds();
+
+    assert_eq!("Iterator::Item", pred.ty().unwrap().syntax().text().to_string());
+    assert_bound("'a", bounds.next());
+
+    let pred = predicates.next().unwrap();
+    let mut bounds = pred.type_bound_list().unwrap().bounds();
+
+    assert_eq!("Iterator::Item", pred.ty().unwrap().syntax().text().to_string());
+    assert_bound("Debug", bounds.next());
+    assert_bound("'a", bounds.next());
+
+    let pred = predicates.next().unwrap();
+    let mut bounds = pred.type_bound_list().unwrap().bounds();
+
+    assert_eq!("<T as Iterator>::Item", pred.ty().unwrap().syntax().text().to_string());
+    assert_bound("Debug", bounds.next());
+    assert_bound("'a", bounds.next());
+
+    let pred = predicates.next().unwrap();
+    let mut bounds = pred.type_bound_list().unwrap().bounds();
+
+    assert!(pred.for_token().is_some());
+    assert_eq!("<'a>", pred.generic_param_list().unwrap().syntax().text().to_string());
+    assert_eq!("F", pred.ty().unwrap().syntax().text().to_string());
+    assert_bound("Fn(&'a str)", bounds.next());
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ast/edit.rs b/src/tools/rust-analyzer/crates/syntax/src/ast/edit.rs
new file mode 100644
index 000000000..15805dfc8
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/ast/edit.rs
@@ -0,0 +1,174 @@
+//! This module contains functions for editing syntax trees. As the trees are
+//! immutable, all function here return a fresh copy of the tree, instead of
+//! doing an in-place modification.
+use std::{fmt, iter, ops};
+
+use crate::{
+    ast::{self, make, AstNode},
+    ted, AstToken, NodeOrToken, SyntaxElement, SyntaxNode, SyntaxToken,
+};
+
+#[derive(Debug, Clone, Copy)]
+pub struct IndentLevel(pub u8);
+
+impl From<u8> for IndentLevel {
+    fn from(level: u8) -> IndentLevel {
+        IndentLevel(level)
+    }
+}
+
+impl fmt::Display for IndentLevel {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let spaces = "                                        ";
+        let buf;
+        let len = self.0 as usize * 4;
+        let indent = if len <= spaces.len() {
+            &spaces[..len]
+        } else {
+            buf = " ".repeat(len);
+            &buf
+        };
+        fmt::Display::fmt(indent, f)
+    }
+}
+
+impl ops::Add<u8> for IndentLevel {
+    type Output = IndentLevel;
+    fn add(self, rhs: u8) -> IndentLevel {
+        IndentLevel(self.0 + rhs)
+    }
+}
+
+impl IndentLevel {
+    pub fn single() -> IndentLevel {
+        IndentLevel(0)
+    }
+    pub fn is_zero(&self) -> bool {
+        self.0 == 0
+    }
+    pub fn from_element(element: &SyntaxElement) -> IndentLevel {
+        match element {
+            rowan::NodeOrToken::Node(it) => IndentLevel::from_node(it),
+            rowan::NodeOrToken::Token(it) => IndentLevel::from_token(it),
+        }
+    }
+
+    pub fn from_node(node: &SyntaxNode) -> IndentLevel {
+        match node.first_token() {
+            Some(it) => Self::from_token(&it),
+            None => IndentLevel(0),
+        }
+    }
+
+    pub fn from_token(token: &SyntaxToken) -> IndentLevel {
+        for ws in prev_tokens(token.clone()).filter_map(ast::Whitespace::cast) {
+            let text = ws.syntax().text();
+            if let Some(pos) = text.rfind('\n') {
+                let level = text[pos + 1..].chars().count() / 4;
+                return IndentLevel(level as u8);
+            }
+        }
+        IndentLevel(0)
+    }
+
+    /// XXX: this intentionally doesn't change the indent of the very first token.
+    /// Ie, in something like
+    /// ```
+    /// fn foo() {
+    ///    92
+    /// }
+    /// ```
+    /// if you indent the block, the `{` token would stay put.
+    pub(super) fn increase_indent(self, node: &SyntaxNode) {
+        let tokens = node.preorder_with_tokens().filter_map(|event| match event {
+            rowan::WalkEvent::Leave(NodeOrToken::Token(it)) => Some(it),
+            _ => None,
+        });
+        for token in tokens {
+            if let Some(ws) = ast::Whitespace::cast(token) {
+                if ws.text().contains('\n') {
+                    let new_ws = make::tokens::whitespace(&format!("{}{}", ws.syntax(), self));
+                    ted::replace(ws.syntax(), &new_ws);
+                }
+            }
+        }
+    }
+
+    pub(super) fn decrease_indent(self, node: &SyntaxNode) {
+        let tokens = node.preorder_with_tokens().filter_map(|event| match event {
+            rowan::WalkEvent::Leave(NodeOrToken::Token(it)) => Some(it),
+            _ => None,
+        });
+        for token in tokens {
+            if let Some(ws) = ast::Whitespace::cast(token) {
+                if ws.text().contains('\n') {
+                    let new_ws = make::tokens::whitespace(
+                        &ws.syntax().text().replace(&format!("\n{}", self), "\n"),
+                    );
+                    ted::replace(ws.syntax(), &new_ws);
+                }
+            }
+        }
+    }
+}
+
+fn prev_tokens(token: SyntaxToken) -> impl Iterator<Item = SyntaxToken> {
+    iter::successors(Some(token), |token| token.prev_token())
+}
+
+/// Soft-deprecated in favor of mutable tree editing API `edit_in_place::Ident`.
+pub trait AstNodeEdit: AstNode + Clone + Sized {
+    fn indent_level(&self) -> IndentLevel {
+        IndentLevel::from_node(self.syntax())
+    }
+    #[must_use]
+    fn indent(&self, level: IndentLevel) -> Self {
+        fn indent_inner(node: &SyntaxNode, level: IndentLevel) -> SyntaxNode {
+            let res = node.clone_subtree().clone_for_update();
+            level.increase_indent(&res);
+            res.clone_subtree()
+        }
+
+        Self::cast(indent_inner(self.syntax(), level)).unwrap()
+    }
+    #[must_use]
+    fn dedent(&self, level: IndentLevel) -> Self {
+        fn dedent_inner(node: &SyntaxNode, level: IndentLevel) -> SyntaxNode {
+            let res = node.clone_subtree().clone_for_update();
+            level.decrease_indent(&res);
+            res.clone_subtree()
+        }
+
+        Self::cast(dedent_inner(self.syntax(), level)).unwrap()
+    }
+    #[must_use]
+    fn reset_indent(&self) -> Self {
+        let level = IndentLevel::from_node(self.syntax());
+        self.dedent(level)
+    }
+}
+
+impl<N: AstNode + Clone> AstNodeEdit for N {}
+
+#[test]
+fn test_increase_indent() {
+    let arm_list = {
+        let arm = make::match_arm(iter::once(make::wildcard_pat().into()), None, make::expr_unit());
+        make::match_arm_list(vec![arm.clone(), arm])
+    };
+    assert_eq!(
+        arm_list.syntax().to_string(),
+        "{
+    _ => (),
+    _ => (),
+}"
+    );
+    let indented = arm_list.indent(IndentLevel(2));
+    assert_eq!(
+        indented.syntax().to_string(),
+        "{
+            _ => (),
+            _ => (),
+        }"
+    );
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ast/edit_in_place.rs b/src/tools/rust-analyzer/crates/syntax/src/ast/edit_in_place.rs
new file mode 100644
index 000000000..e3e928aec
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/ast/edit_in_place.rs
@@ -0,0 +1,717 @@
+//! Structural editing for ast.
+
+use std::iter::{empty, successors};
+
+use parser::{SyntaxKind, T};
+use rowan::SyntaxElement;
+
+use crate::{
+    algo::{self, neighbor},
+    ast::{self, edit::IndentLevel, make, HasGenericParams},
+    ted::{self, Position},
+    AstNode, AstToken, Direction,
+    SyntaxKind::{ATTR, COMMENT, WHITESPACE},
+    SyntaxNode,
+};
+
+use super::HasName;
+
+pub trait GenericParamsOwnerEdit: ast::HasGenericParams {
+    fn get_or_create_generic_param_list(&self) -> ast::GenericParamList;
+    fn get_or_create_where_clause(&self) -> ast::WhereClause;
+}
+
+impl GenericParamsOwnerEdit for ast::Fn {
+    fn get_or_create_generic_param_list(&self) -> ast::GenericParamList {
+        match self.generic_param_list() {
+            Some(it) => it,
+            None => {
+                let position = if let Some(name) = self.name() {
+                    Position::after(name.syntax)
+                } else if let Some(fn_token) = self.fn_token() {
+                    Position::after(fn_token)
+                } else if let Some(param_list) = self.param_list() {
+                    Position::before(param_list.syntax)
+                } else {
+                    Position::last_child_of(self.syntax())
+                };
+                create_generic_param_list(position)
+            }
+        }
+    }
+
+    fn get_or_create_where_clause(&self) -> ast::WhereClause {
+        if self.where_clause().is_none() {
+            let position = if let Some(ty) = self.ret_type() {
+                Position::after(ty.syntax())
+            } else if let Some(param_list) = self.param_list() {
+                Position::after(param_list.syntax())
+            } else {
+                Position::last_child_of(self.syntax())
+            };
+            create_where_clause(position);
+        }
+        self.where_clause().unwrap()
+    }
+}
+
+impl GenericParamsOwnerEdit for ast::Impl {
+    fn get_or_create_generic_param_list(&self) -> ast::GenericParamList {
+        match self.generic_param_list() {
+            Some(it) => it,
+            None => {
+                let position = match self.impl_token() {
+                    Some(imp_token) => Position::after(imp_token),
+                    None => Position::last_child_of(self.syntax()),
+                };
+                create_generic_param_list(position)
+            }
+        }
+    }
+
+    fn get_or_create_where_clause(&self) -> ast::WhereClause {
+        if self.where_clause().is_none() {
+            let position = match self.assoc_item_list() {
+                Some(items) => Position::before(items.syntax()),
+                None => Position::last_child_of(self.syntax()),
+            };
+            create_where_clause(position);
+        }
+        self.where_clause().unwrap()
+    }
+}
+
+impl GenericParamsOwnerEdit for ast::Trait {
+    fn get_or_create_generic_param_list(&self) -> ast::GenericParamList {
+        match self.generic_param_list() {
+            Some(it) => it,
+            None => {
+                let position = if let Some(name) = self.name() {
+                    Position::after(name.syntax)
+                } else if let Some(trait_token) = self.trait_token() {
+                    Position::after(trait_token)
+                } else {
+                    Position::last_child_of(self.syntax())
+                };
+                create_generic_param_list(position)
+            }
+        }
+    }
+
+    fn get_or_create_where_clause(&self) -> ast::WhereClause {
+        if self.where_clause().is_none() {
+            let position = match self.assoc_item_list() {
+                Some(items) => Position::before(items.syntax()),
+                None => Position::last_child_of(self.syntax()),
+            };
+            create_where_clause(position);
+        }
+        self.where_clause().unwrap()
+    }
+}
+
+impl GenericParamsOwnerEdit for ast::Struct {
+    fn get_or_create_generic_param_list(&self) -> ast::GenericParamList {
+        match self.generic_param_list() {
+            Some(it) => it,
+            None => {
+                let position = if let Some(name) = self.name() {
+                    Position::after(name.syntax)
+                } else if let Some(struct_token) = self.struct_token() {
+                    Position::after(struct_token)
+                } else {
+                    Position::last_child_of(self.syntax())
+                };
+                create_generic_param_list(position)
+            }
+        }
+    }
+
+    fn get_or_create_where_clause(&self) -> ast::WhereClause {
+        if self.where_clause().is_none() {
+            let tfl = self.field_list().and_then(|fl| match fl {
+                ast::FieldList::RecordFieldList(_) => None,
+                ast::FieldList::TupleFieldList(it) => Some(it),
+            });
+            let position = if let Some(tfl) = tfl {
+                Position::after(tfl.syntax())
+            } else if let Some(gpl) = self.generic_param_list() {
+                Position::after(gpl.syntax())
+            } else if let Some(name) = self.name() {
+                Position::after(name.syntax())
+            } else {
+                Position::last_child_of(self.syntax())
+            };
+            create_where_clause(position);
+        }
+        self.where_clause().unwrap()
+    }
+}
+
+impl GenericParamsOwnerEdit for ast::Enum {
+    fn get_or_create_generic_param_list(&self) -> ast::GenericParamList {
+        match self.generic_param_list() {
+            Some(it) => it,
+            None => {
+                let position = if let Some(name) = self.name() {
+                    Position::after(name.syntax)
+                } else if let Some(enum_token) = self.enum_token() {
+                    Position::after(enum_token)
+                } else {
+                    Position::last_child_of(self.syntax())
+                };
+                create_generic_param_list(position)
+            }
+        }
+    }
+
+    fn get_or_create_where_clause(&self) -> ast::WhereClause {
+        if self.where_clause().is_none() {
+            let position = if let Some(gpl) = self.generic_param_list() {
+                Position::after(gpl.syntax())
+            } else if let Some(name) = self.name() {
+                Position::after(name.syntax())
+            } else {
+                Position::last_child_of(self.syntax())
+            };
+            create_where_clause(position);
+        }
+        self.where_clause().unwrap()
+    }
+}
+
+fn create_where_clause(position: Position) {
+    let where_clause = make::where_clause(empty()).clone_for_update();
+    ted::insert(position, where_clause.syntax());
+}
+
+fn create_generic_param_list(position: Position) -> ast::GenericParamList {
+    let gpl = make::generic_param_list(empty()).clone_for_update();
+    ted::insert_raw(position, gpl.syntax());
+    gpl
+}
+
+pub trait AttrsOwnerEdit: ast::HasAttrs {
+    fn remove_attrs_and_docs(&self) {
+        remove_attrs_and_docs(self.syntax());
+
+        fn remove_attrs_and_docs(node: &SyntaxNode) {
+            let mut remove_next_ws = false;
+            for child in node.children_with_tokens() {
+                match child.kind() {
+                    ATTR | COMMENT => {
+                        remove_next_ws = true;
+                        child.detach();
+                        continue;
+                    }
+                    WHITESPACE if remove_next_ws => {
+                        child.detach();
+                    }
+                    _ => (),
+                }
+                remove_next_ws = false;
+            }
+        }
+    }
+}
+
+impl<T: ast::HasAttrs> AttrsOwnerEdit for T {}
+
+impl ast::GenericParamList {
+    pub fn add_generic_param(&self, generic_param: ast::GenericParam) {
+        match self.generic_params().last() {
+            Some(last_param) => {
+                let position = Position::after(last_param.syntax());
+                let elements = vec![
+                    make::token(T![,]).into(),
+                    make::tokens::single_space().into(),
+                    generic_param.syntax().clone().into(),
+                ];
+                ted::insert_all(position, elements);
+            }
+            None => {
+                let after_l_angle = Position::after(self.l_angle_token().unwrap());
+                ted::insert(after_l_angle, generic_param.syntax());
+            }
+        }
+    }
+}
+
+impl ast::WhereClause {
+    pub fn add_predicate(&self, predicate: ast::WherePred) {
+        if let Some(pred) = self.predicates().last() {
+            if !pred.syntax().siblings_with_tokens(Direction::Next).any(|it| it.kind() == T![,]) {
+                ted::append_child_raw(self.syntax(), make::token(T![,]));
+            }
+        }
+        ted::append_child(self.syntax(), predicate.syntax());
+    }
+}
+
+impl ast::TypeBoundList {
+    pub fn remove(&self) {
+        match self.syntax().siblings_with_tokens(Direction::Prev).find(|it| it.kind() == T![:]) {
+            Some(colon) => ted::remove_all(colon..=self.syntax().clone().into()),
+            None => ted::remove(self.syntax()),
+        }
+    }
+}
+
+impl ast::PathSegment {
+    pub fn get_or_create_generic_arg_list(&self) -> ast::GenericArgList {
+        if self.generic_arg_list().is_none() {
+            let arg_list = make::generic_arg_list().clone_for_update();
+            ted::append_child(self.syntax(), arg_list.syntax());
+        }
+        self.generic_arg_list().unwrap()
+    }
+}
+
+impl ast::UseTree {
+    pub fn remove(&self) {
+        for dir in [Direction::Next, Direction::Prev] {
+            if let Some(next_use_tree) = neighbor(self, dir) {
+                let separators = self
+                    .syntax()
+                    .siblings_with_tokens(dir)
+                    .skip(1)
+                    .take_while(|it| it.as_node() != Some(next_use_tree.syntax()));
+                ted::remove_all_iter(separators);
+                break;
+            }
+        }
+        ted::remove(self.syntax());
+    }
+
+    pub fn get_or_create_use_tree_list(&self) -> ast::UseTreeList {
+        match self.use_tree_list() {
+            Some(it) => it,
+            None => {
+                let position = Position::last_child_of(self.syntax());
+                let use_tree_list = make::use_tree_list(empty()).clone_for_update();
+                let mut elements = Vec::with_capacity(2);
+                if self.coloncolon_token().is_none() {
+                    elements.push(make::token(T![::]).into());
+                }
+                elements.push(use_tree_list.syntax().clone().into());
+                ted::insert_all_raw(position, elements);
+                use_tree_list
+            }
+        }
+    }
+
+    /// Splits off the given prefix, making it the path component of the use tree,
+    /// appending the rest of the path to all UseTreeList items.
+    ///
+    /// # Examples
+    ///
+    /// `prefix$0::suffix` -> `prefix::{suffix}`
+    ///
+    /// `prefix$0` -> `prefix::{self}`
+    ///
+    /// `prefix$0::*` -> `prefix::{*}`
+    pub fn split_prefix(&self, prefix: &ast::Path) {
+        debug_assert_eq!(self.path(), Some(prefix.top_path()));
+        let path = self.path().unwrap();
+        if &path == prefix && self.use_tree_list().is_none() {
+            if self.star_token().is_some() {
+                // path$0::* -> *
+                self.coloncolon_token().map(ted::remove);
+                ted::remove(prefix.syntax());
+            } else {
+                // path$0 -> self
+                let self_suffix =
+                    make::path_unqualified(make::path_segment_self()).clone_for_update();
+                ted::replace(path.syntax(), self_suffix.syntax());
+            }
+        } else if split_path_prefix(prefix).is_none() {
+            return;
+        }
+        // At this point, prefix path is detached; _self_ use tree has suffix path.
+        // Next, transform 'suffix' use tree into 'prefix::{suffix}'
+        let subtree = self.clone_subtree().clone_for_update();
+        ted::remove_all_iter(self.syntax().children_with_tokens());
+        ted::insert(Position::first_child_of(self.syntax()), prefix.syntax());
+        self.get_or_create_use_tree_list().add_use_tree(subtree);
+
+        fn split_path_prefix(prefix: &ast::Path) -> Option<()> {
+            let parent = prefix.parent_path()?;
+            let segment = parent.segment()?;
+            if algo::has_errors(segment.syntax()) {
+                return None;
+            }
+            for p in successors(parent.parent_path(), |it| it.parent_path()) {
+                p.segment()?;
+            }
+            prefix.parent_path().and_then(|p| p.coloncolon_token()).map(ted::remove);
+            ted::remove(prefix.syntax());
+            Some(())
+        }
+    }
+}
+
+impl ast::UseTreeList {
+    pub fn add_use_tree(&self, use_tree: ast::UseTree) {
+        let (position, elements) = match self.use_trees().last() {
+            Some(last_tree) => (
+                Position::after(last_tree.syntax()),
+                vec![
+                    make::token(T![,]).into(),
+                    make::tokens::single_space().into(),
+                    use_tree.syntax.into(),
+                ],
+            ),
+            None => {
+                let position = match self.l_curly_token() {
+                    Some(l_curly) => Position::after(l_curly),
+                    None => Position::last_child_of(self.syntax()),
+                };
+                (position, vec![use_tree.syntax.into()])
+            }
+        };
+        ted::insert_all_raw(position, elements);
+    }
+}
+
+impl ast::Use {
+    pub fn remove(&self) {
+        let next_ws = self
+            .syntax()
+            .next_sibling_or_token()
+            .and_then(|it| it.into_token())
+            .and_then(ast::Whitespace::cast);
+        if let Some(next_ws) = next_ws {
+            let ws_text = next_ws.syntax().text();
+            if let Some(rest) = ws_text.strip_prefix('\n') {
+                if rest.is_empty() {
+                    ted::remove(next_ws.syntax());
+                } else {
+                    ted::replace(next_ws.syntax(), make::tokens::whitespace(rest));
+                }
+            }
+        }
+        ted::remove(self.syntax());
+    }
+}
+
+impl ast::Impl {
+    pub fn get_or_create_assoc_item_list(&self) -> ast::AssocItemList {
+        if self.assoc_item_list().is_none() {
+            let assoc_item_list = make::assoc_item_list().clone_for_update();
+            ted::append_child(self.syntax(), assoc_item_list.syntax());
+        }
+        self.assoc_item_list().unwrap()
+    }
+}
+
+impl ast::AssocItemList {
+    pub fn add_item(&self, item: ast::AssocItem) {
+        let (indent, position, whitespace) = match self.assoc_items().last() {
+            Some(last_item) => (
+                IndentLevel::from_node(last_item.syntax()),
+                Position::after(last_item.syntax()),
+                "\n\n",
+            ),
+            None => match self.l_curly_token() {
+                Some(l_curly) => {
+                    normalize_ws_between_braces(self.syntax());
+                    (IndentLevel::from_token(&l_curly) + 1, Position::after(&l_curly), "\n")
+                }
+                None => (IndentLevel::single(), Position::last_child_of(self.syntax()), "\n"),
+            },
+        };
+        let elements: Vec<SyntaxElement<_>> = vec![
+            make::tokens::whitespace(&format!("{}{}", whitespace, indent)).into(),
+            item.syntax().clone().into(),
+        ];
+        ted::insert_all(position, elements);
+    }
+}
+
+impl ast::Fn {
+    pub fn get_or_create_body(&self) -> ast::BlockExpr {
+        if self.body().is_none() {
+            let body = make::ext::empty_block_expr().clone_for_update();
+            match self.semicolon_token() {
+                Some(semi) => {
+                    ted::replace(semi, body.syntax());
+                    ted::insert(Position::before(body.syntax), make::tokens::single_space());
+                }
+                None => ted::append_child(self.syntax(), body.syntax()),
+            }
+        }
+        self.body().unwrap()
+    }
+}
+
+impl ast::MatchArm {
+    pub fn remove(&self) {
+        if let Some(sibling) = self.syntax().prev_sibling_or_token() {
+            if sibling.kind() == SyntaxKind::WHITESPACE {
+                ted::remove(sibling);
+            }
+        }
+        if let Some(sibling) = self.syntax().next_sibling_or_token() {
+            if sibling.kind() == T![,] {
+                ted::remove(sibling);
+            }
+        }
+        ted::remove(self.syntax());
+    }
+}
+
+impl ast::MatchArmList {
+    pub fn add_arm(&self, arm: ast::MatchArm) {
+        normalize_ws_between_braces(self.syntax());
+        let mut elements = Vec::new();
+        let position = match self.arms().last() {
+            Some(last_arm) => {
+                if needs_comma(&last_arm) {
+                    ted::append_child(last_arm.syntax(), make::token(SyntaxKind::COMMA));
+                }
+                Position::after(last_arm.syntax().clone())
+            }
+            None => match self.l_curly_token() {
+                Some(it) => Position::after(it),
+                None => Position::last_child_of(self.syntax()),
+            },
+        };
+        let indent = IndentLevel::from_node(self.syntax()) + 1;
+        elements.push(make::tokens::whitespace(&format!("\n{}", indent)).into());
+        elements.push(arm.syntax().clone().into());
+        if needs_comma(&arm) {
+            ted::append_child(arm.syntax(), make::token(SyntaxKind::COMMA));
+        }
+        ted::insert_all(position, elements);
+
+        fn needs_comma(arm: &ast::MatchArm) -> bool {
+            arm.expr().map_or(false, |e| !e.is_block_like()) && arm.comma_token().is_none()
+        }
+    }
+}
+
+impl ast::RecordExprFieldList {
+    pub fn add_field(&self, field: ast::RecordExprField) {
+        let is_multiline = self.syntax().text().contains_char('\n');
+        let whitespace = if is_multiline {
+            let indent = IndentLevel::from_node(self.syntax()) + 1;
+            make::tokens::whitespace(&format!("\n{}", indent))
+        } else {
+            make::tokens::single_space()
+        };
+
+        if is_multiline {
+            normalize_ws_between_braces(self.syntax());
+        }
+
+        let position = match self.fields().last() {
+            Some(last_field) => {
+                let comma = match last_field
+                    .syntax()
+                    .siblings_with_tokens(Direction::Next)
+                    .filter_map(|it| it.into_token())
+                    .find(|it| it.kind() == T![,])
+                {
+                    Some(it) => it,
+                    None => {
+                        let comma = ast::make::token(T![,]);
+                        ted::insert(Position::after(last_field.syntax()), &comma);
+                        comma
+                    }
+                };
+                Position::after(comma)
+            }
+            None => match self.l_curly_token() {
+                Some(it) => Position::after(it),
+                None => Position::last_child_of(self.syntax()),
+            },
+        };
+
+        ted::insert_all(position, vec![whitespace.into(), field.syntax().clone().into()]);
+        if is_multiline {
+            ted::insert(Position::after(field.syntax()), ast::make::token(T![,]));
+        }
+    }
+}
+
+impl ast::RecordExprField {
+    /// This will either replace the initializer, or in the case that this is a shorthand convert
+    /// the initializer into the name ref and insert the expr as the new initializer.
+    pub fn replace_expr(&self, expr: ast::Expr) {
+        if self.name_ref().is_some() {
+            match self.expr() {
+                Some(prev) => ted::replace(prev.syntax(), expr.syntax()),
+                None => ted::append_child(self.syntax(), expr.syntax()),
+            }
+            return;
+        }
+        // this is a shorthand
+        if let Some(ast::Expr::PathExpr(path_expr)) = self.expr() {
+            if let Some(path) = path_expr.path() {
+                if let Some(name_ref) = path.as_single_name_ref() {
+                    path_expr.syntax().detach();
+                    let children = vec![
+                        name_ref.syntax().clone().into(),
+                        ast::make::token(T![:]).into(),
+                        ast::make::tokens::single_space().into(),
+                        expr.syntax().clone().into(),
+                    ];
+                    ted::insert_all_raw(Position::last_child_of(self.syntax()), children);
+                }
+            }
+        }
+    }
+}
+
+impl ast::RecordPatFieldList {
+    pub fn add_field(&self, field: ast::RecordPatField) {
+        let is_multiline = self.syntax().text().contains_char('\n');
+        let whitespace = if is_multiline {
+            let indent = IndentLevel::from_node(self.syntax()) + 1;
+            make::tokens::whitespace(&format!("\n{}", indent))
+        } else {
+            make::tokens::single_space()
+        };
+
+        if is_multiline {
+            normalize_ws_between_braces(self.syntax());
+        }
+
+        let position = match self.fields().last() {
+            Some(last_field) => {
+                let comma = match last_field
+                    .syntax()
+                    .siblings_with_tokens(Direction::Next)
+                    .filter_map(|it| it.into_token())
+                    .find(|it| it.kind() == T![,])
+                {
+                    Some(it) => it,
+                    None => {
+                        let comma = ast::make::token(T![,]);
+                        ted::insert(Position::after(last_field.syntax()), &comma);
+                        comma
+                    }
+                };
+                Position::after(comma)
+            }
+            None => match self.l_curly_token() {
+                Some(it) => Position::after(it),
+                None => Position::last_child_of(self.syntax()),
+            },
+        };
+
+        ted::insert_all(position, vec![whitespace.into(), field.syntax().clone().into()]);
+        if is_multiline {
+            ted::insert(Position::after(field.syntax()), ast::make::token(T![,]));
+        }
+    }
+}
+impl ast::StmtList {
+    pub fn push_front(&self, statement: ast::Stmt) {
+        ted::insert(Position::after(self.l_curly_token().unwrap()), statement.syntax());
+    }
+}
+
+fn normalize_ws_between_braces(node: &SyntaxNode) -> Option<()> {
+    let l = node
+        .children_with_tokens()
+        .filter_map(|it| it.into_token())
+        .find(|it| it.kind() == T!['{'])?;
+    let r = node
+        .children_with_tokens()
+        .filter_map(|it| it.into_token())
+        .find(|it| it.kind() == T!['}'])?;
+
+    let indent = IndentLevel::from_node(node);
+
+    match l.next_sibling_or_token() {
+        Some(ws) if ws.kind() == SyntaxKind::WHITESPACE => {
+            if ws.next_sibling_or_token()?.into_token()? == r {
+                ted::replace(ws, make::tokens::whitespace(&format!("\n{}", indent)));
+            }
+        }
+        Some(ws) if ws.kind() == T!['}'] => {
+            ted::insert(Position::after(l), make::tokens::whitespace(&format!("\n{}", indent)));
+        }
+        _ => (),
+    }
+    Some(())
+}
+
+pub trait Indent: AstNode + Clone + Sized {
+    fn indent_level(&self) -> IndentLevel {
+        IndentLevel::from_node(self.syntax())
+    }
+    fn indent(&self, by: IndentLevel) {
+        by.increase_indent(self.syntax());
+    }
+    fn dedent(&self, by: IndentLevel) {
+        by.decrease_indent(self.syntax());
+    }
+    fn reindent_to(&self, target_level: IndentLevel) {
+        let current_level = IndentLevel::from_node(self.syntax());
+        self.dedent(current_level);
+        self.indent(target_level);
+    }
+}
+
+impl<N: AstNode + Clone> Indent for N {}
+
+#[cfg(test)]
+mod tests {
+    use std::fmt;
+
+    use crate::SourceFile;
+
+    use super::*;
+
+    fn ast_mut_from_text<N: AstNode>(text: &str) -> N {
+        let parse = SourceFile::parse(text);
+        parse.tree().syntax().descendants().find_map(N::cast).unwrap().clone_for_update()
+    }
+
+    #[test]
+    fn test_create_generic_param_list() {
+        fn check_create_gpl<N: GenericParamsOwnerEdit + fmt::Display>(before: &str, after: &str) {
+            let gpl_owner = ast_mut_from_text::<N>(before);
+            gpl_owner.get_or_create_generic_param_list();
+            assert_eq!(gpl_owner.to_string(), after);
+        }
+
+        check_create_gpl::<ast::Fn>("fn foo", "fn foo<>");
+        check_create_gpl::<ast::Fn>("fn foo() {}", "fn foo<>() {}");
+
+        check_create_gpl::<ast::Impl>("impl", "impl<>");
+        check_create_gpl::<ast::Impl>("impl Struct {}", "impl<> Struct {}");
+        check_create_gpl::<ast::Impl>("impl Trait for Struct {}", "impl<> Trait for Struct {}");
+
+        check_create_gpl::<ast::Trait>("trait Trait<>", "trait Trait<>");
+        check_create_gpl::<ast::Trait>("trait Trait<> {}", "trait Trait<> {}");
+
+        check_create_gpl::<ast::Struct>("struct A", "struct A<>");
+        check_create_gpl::<ast::Struct>("struct A;", "struct A<>;");
+        check_create_gpl::<ast::Struct>("struct A();", "struct A<>();");
+        check_create_gpl::<ast::Struct>("struct A {}", "struct A<> {}");
+
+        check_create_gpl::<ast::Enum>("enum E", "enum E<>");
+        check_create_gpl::<ast::Enum>("enum E {", "enum E<> {");
+    }
+
+    #[test]
+    fn test_increase_indent() {
+        let arm_list = ast_mut_from_text::<ast::Fn>(
+            "fn foo() {
+    ;
+    ;
+}",
+        );
+        arm_list.indent(IndentLevel(2));
+        assert_eq!(
+            arm_list.to_string(),
+            "fn foo() {
+            ;
+            ;
+        }",
+        );
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ast/expr_ext.rs b/src/tools/rust-analyzer/crates/syntax/src/ast/expr_ext.rs
new file mode 100644
index 000000000..db66d08a7
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/ast/expr_ext.rs
@@ -0,0 +1,410 @@
+//! Various extension methods to ast Expr Nodes, which are hard to code-generate.
+//!
+//! These methods should only do simple, shallow tasks related to the syntax of the node itself.
+
+use crate::{
+    ast::{
+        self,
+        operators::{ArithOp, BinaryOp, CmpOp, LogicOp, Ordering, RangeOp, UnaryOp},
+        support, AstChildren, AstNode,
+    },
+    AstToken,
+    SyntaxKind::*,
+    SyntaxNode, SyntaxToken, T,
+};
+
+impl ast::HasAttrs for ast::Expr {}
+
+impl ast::Expr {
+    pub fn is_block_like(&self) -> bool {
+        matches!(
+            self,
+            ast::Expr::IfExpr(_)
+                | ast::Expr::LoopExpr(_)
+                | ast::Expr::ForExpr(_)
+                | ast::Expr::WhileExpr(_)
+                | ast::Expr::BlockExpr(_)
+                | ast::Expr::MatchExpr(_)
+        )
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum ElseBranch {
+    Block(ast::BlockExpr),
+    IfExpr(ast::IfExpr),
+}
+
+impl From<ast::BlockExpr> for ElseBranch {
+    fn from(block_expr: ast::BlockExpr) -> Self {
+        Self::Block(block_expr)
+    }
+}
+
+impl From<ast::IfExpr> for ElseBranch {
+    fn from(if_expr: ast::IfExpr) -> Self {
+        Self::IfExpr(if_expr)
+    }
+}
+
+impl ast::IfExpr {
+    pub fn then_branch(&self) -> Option<ast::BlockExpr> {
+        self.children_after_condition().next()
+    }
+
+    pub fn else_branch(&self) -> Option<ElseBranch> {
+        let res = match self.children_after_condition().nth(1) {
+            Some(block) => ElseBranch::Block(block),
+            None => {
+                let elif = self.children_after_condition().next()?;
+                ElseBranch::IfExpr(elif)
+            }
+        };
+        Some(res)
+    }
+
+    fn children_after_condition<N: AstNode>(&self) -> impl Iterator<Item = N> {
+        self.syntax().children().skip(1).filter_map(N::cast)
+    }
+}
+
+#[test]
+fn if_block_condition() {
+    let parse = ast::SourceFile::parse(
+        r#"
+        fn test() {
+            if { true } { "if" }
+            else if { false } { "first elif" }
+            else if true { "second elif" }
+            else if (true) { "third elif" }
+            else { "else" }
+        }
+        "#,
+    );
+    let if_ = parse.tree().syntax().descendants().find_map(ast::IfExpr::cast).unwrap();
+    assert_eq!(if_.then_branch().unwrap().syntax().text(), r#"{ "if" }"#);
+    let elif = match if_.else_branch().unwrap() {
+        ElseBranch::IfExpr(elif) => elif,
+        ElseBranch::Block(_) => panic!("should be `else if`"),
+    };
+    assert_eq!(elif.then_branch().unwrap().syntax().text(), r#"{ "first elif" }"#);
+    let elif = match elif.else_branch().unwrap() {
+        ElseBranch::IfExpr(elif) => elif,
+        ElseBranch::Block(_) => panic!("should be `else if`"),
+    };
+    assert_eq!(elif.then_branch().unwrap().syntax().text(), r#"{ "second elif" }"#);
+    let elif = match elif.else_branch().unwrap() {
+        ElseBranch::IfExpr(elif) => elif,
+        ElseBranch::Block(_) => panic!("should be `else if`"),
+    };
+    assert_eq!(elif.then_branch().unwrap().syntax().text(), r#"{ "third elif" }"#);
+    let else_ = match elif.else_branch().unwrap() {
+        ElseBranch::Block(else_) => else_,
+        ElseBranch::IfExpr(_) => panic!("should be `else`"),
+    };
+    assert_eq!(else_.syntax().text(), r#"{ "else" }"#);
+}
+
+#[test]
+fn if_condition_with_if_inside() {
+    let parse = ast::SourceFile::parse(
+        r#"
+        fn test() {
+            if if true { true } else { false } { "if" }
+            else { "else" }
+        }
+        "#,
+    );
+    let if_ = parse.tree().syntax().descendants().find_map(ast::IfExpr::cast).unwrap();
+    assert_eq!(if_.then_branch().unwrap().syntax().text(), r#"{ "if" }"#);
+    let else_ = match if_.else_branch().unwrap() {
+        ElseBranch::Block(else_) => else_,
+        ElseBranch::IfExpr(_) => panic!("should be `else`"),
+    };
+    assert_eq!(else_.syntax().text(), r#"{ "else" }"#);
+}
+
+impl ast::PrefixExpr {
+    pub fn op_kind(&self) -> Option<UnaryOp> {
+        let res = match self.op_token()?.kind() {
+            T![*] => UnaryOp::Deref,
+            T![!] => UnaryOp::Not,
+            T![-] => UnaryOp::Neg,
+            _ => return None,
+        };
+        Some(res)
+    }
+
+    pub fn op_token(&self) -> Option<SyntaxToken> {
+        self.syntax().first_child_or_token()?.into_token()
+    }
+}
+
+impl ast::BinExpr {
+    pub fn op_details(&self) -> Option<(SyntaxToken, BinaryOp)> {
+        self.syntax().children_with_tokens().filter_map(|it| it.into_token()).find_map(|c| {
+            #[rustfmt::skip]
+            let bin_op = match c.kind() {
+                T![||] => BinaryOp::LogicOp(LogicOp::Or),
+                T![&&] => BinaryOp::LogicOp(LogicOp::And),
+
+                T![==] => BinaryOp::CmpOp(CmpOp::Eq { negated: false }),
+                T![!=] => BinaryOp::CmpOp(CmpOp::Eq { negated: true }),
+                T![<=] => BinaryOp::CmpOp(CmpOp::Ord { ordering: Ordering::Less,    strict: false }),
+                T![>=] => BinaryOp::CmpOp(CmpOp::Ord { ordering: Ordering::Greater, strict: false }),
+                T![<]  => BinaryOp::CmpOp(CmpOp::Ord { ordering: Ordering::Less,    strict: true }),
+                T![>]  => BinaryOp::CmpOp(CmpOp::Ord { ordering: Ordering::Greater, strict: true }),
+
+                T![+]  => BinaryOp::ArithOp(ArithOp::Add),
+                T![*]  => BinaryOp::ArithOp(ArithOp::Mul),
+                T![-]  => BinaryOp::ArithOp(ArithOp::Sub),
+                T![/]  => BinaryOp::ArithOp(ArithOp::Div),
+                T![%]  => BinaryOp::ArithOp(ArithOp::Rem),
+                T![<<] => BinaryOp::ArithOp(ArithOp::Shl),
+                T![>>] => BinaryOp::ArithOp(ArithOp::Shr),
+                T![^]  => BinaryOp::ArithOp(ArithOp::BitXor),
+                T![|]  => BinaryOp::ArithOp(ArithOp::BitOr),
+                T![&]  => BinaryOp::ArithOp(ArithOp::BitAnd),
+
+                T![=]   => BinaryOp::Assignment { op: None },
+                T![+=]  => BinaryOp::Assignment { op: Some(ArithOp::Add) },
+                T![*=]  => BinaryOp::Assignment { op: Some(ArithOp::Mul) },
+                T![-=]  => BinaryOp::Assignment { op: Some(ArithOp::Sub) },
+                T![/=]  => BinaryOp::Assignment { op: Some(ArithOp::Div) },
+                T![%=]  => BinaryOp::Assignment { op: Some(ArithOp::Rem) },
+                T![<<=] => BinaryOp::Assignment { op: Some(ArithOp::Shl) },
+                T![>>=] => BinaryOp::Assignment { op: Some(ArithOp::Shr) },
+                T![^=]  => BinaryOp::Assignment { op: Some(ArithOp::BitXor) },
+                T![|=]  => BinaryOp::Assignment { op: Some(ArithOp::BitOr) },
+                T![&=]  => BinaryOp::Assignment { op: Some(ArithOp::BitAnd) },
+
+                _ => return None,
+            };
+            Some((c, bin_op))
+        })
+    }
+
+    pub fn op_kind(&self) -> Option<BinaryOp> {
+        self.op_details().map(|t| t.1)
+    }
+
+    pub fn op_token(&self) -> Option<SyntaxToken> {
+        self.op_details().map(|t| t.0)
+    }
+
+    pub fn lhs(&self) -> Option<ast::Expr> {
+        support::children(self.syntax()).next()
+    }
+
+    pub fn rhs(&self) -> Option<ast::Expr> {
+        support::children(self.syntax()).nth(1)
+    }
+
+    pub fn sub_exprs(&self) -> (Option<ast::Expr>, Option<ast::Expr>) {
+        let mut children = support::children(self.syntax());
+        let first = children.next();
+        let second = children.next();
+        (first, second)
+    }
+}
+
+impl ast::RangeExpr {
+    fn op_details(&self) -> Option<(usize, SyntaxToken, RangeOp)> {
+        self.syntax().children_with_tokens().enumerate().find_map(|(ix, child)| {
+            let token = child.into_token()?;
+            let bin_op = match token.kind() {
+                T![..] => RangeOp::Exclusive,
+                T![..=] => RangeOp::Inclusive,
+                _ => return None,
+            };
+            Some((ix, token, bin_op))
+        })
+    }
+
+    pub fn op_kind(&self) -> Option<RangeOp> {
+        self.op_details().map(|t| t.2)
+    }
+
+    pub fn op_token(&self) -> Option<SyntaxToken> {
+        self.op_details().map(|t| t.1)
+    }
+
+    pub fn start(&self) -> Option<ast::Expr> {
+        let op_ix = self.op_details()?.0;
+        self.syntax()
+            .children_with_tokens()
+            .take(op_ix)
+            .find_map(|it| ast::Expr::cast(it.into_node()?))
+    }
+
+    pub fn end(&self) -> Option<ast::Expr> {
+        let op_ix = self.op_details()?.0;
+        self.syntax()
+            .children_with_tokens()
+            .skip(op_ix + 1)
+            .find_map(|it| ast::Expr::cast(it.into_node()?))
+    }
+}
+
+impl ast::IndexExpr {
+    pub fn base(&self) -> Option<ast::Expr> {
+        support::children(self.syntax()).next()
+    }
+    pub fn index(&self) -> Option<ast::Expr> {
+        support::children(self.syntax()).nth(1)
+    }
+}
+
+pub enum ArrayExprKind {
+    Repeat { initializer: Option<ast::Expr>, repeat: Option<ast::Expr> },
+    ElementList(AstChildren<ast::Expr>),
+}
+
+impl ast::ArrayExpr {
+    pub fn kind(&self) -> ArrayExprKind {
+        if self.is_repeat() {
+            ArrayExprKind::Repeat {
+                initializer: support::children(self.syntax()).next(),
+                repeat: support::children(self.syntax()).nth(1),
+            }
+        } else {
+            ArrayExprKind::ElementList(support::children(self.syntax()))
+        }
+    }
+
+    fn is_repeat(&self) -> bool {
+        self.semicolon_token().is_some()
+    }
+}
+
+#[derive(Clone, Debug, PartialEq, Eq, Hash)]
+pub enum LiteralKind {
+    String(ast::String),
+    ByteString(ast::ByteString),
+    IntNumber(ast::IntNumber),
+    FloatNumber(ast::FloatNumber),
+    Char(ast::Char),
+    Byte(ast::Byte),
+    Bool(bool),
+}
+
+impl ast::Literal {
+    pub fn token(&self) -> SyntaxToken {
+        self.syntax()
+            .children_with_tokens()
+            .find(|e| e.kind() != ATTR && !e.kind().is_trivia())
+            .and_then(|e| e.into_token())
+            .unwrap()
+    }
+
+    pub fn kind(&self) -> LiteralKind {
+        let token = self.token();
+
+        if let Some(t) = ast::IntNumber::cast(token.clone()) {
+            return LiteralKind::IntNumber(t);
+        }
+        if let Some(t) = ast::FloatNumber::cast(token.clone()) {
+            return LiteralKind::FloatNumber(t);
+        }
+        if let Some(t) = ast::String::cast(token.clone()) {
+            return LiteralKind::String(t);
+        }
+        if let Some(t) = ast::ByteString::cast(token.clone()) {
+            return LiteralKind::ByteString(t);
+        }
+        if let Some(t) = ast::Char::cast(token.clone()) {
+            return LiteralKind::Char(t);
+        }
+        if let Some(t) = ast::Byte::cast(token.clone()) {
+            return LiteralKind::Byte(t);
+        }
+
+        match token.kind() {
+            T![true] => LiteralKind::Bool(true),
+            T![false] => LiteralKind::Bool(false),
+            _ => unreachable!(),
+        }
+    }
+}
+
+pub enum BlockModifier {
+    Async(SyntaxToken),
+    Unsafe(SyntaxToken),
+    Try(SyntaxToken),
+    Const(SyntaxToken),
+    Label(ast::Label),
+}
+
+impl ast::BlockExpr {
+    pub fn modifier(&self) -> Option<BlockModifier> {
+        self.async_token()
+            .map(BlockModifier::Async)
+            .or_else(|| self.unsafe_token().map(BlockModifier::Unsafe))
+            .or_else(|| self.try_token().map(BlockModifier::Try))
+            .or_else(|| self.const_token().map(BlockModifier::Const))
+            .or_else(|| self.label().map(BlockModifier::Label))
+    }
+    /// false if the block is an intrinsic part of the syntax and can't be
+    /// replaced with arbitrary expression.
+    ///
+    /// ```not_rust
+    /// fn foo() { not_stand_alone }
+    /// const FOO: () = { stand_alone };
+    /// ```
+    pub fn is_standalone(&self) -> bool {
+        let parent = match self.syntax().parent() {
+            Some(it) => it,
+            None => return true,
+        };
+        !matches!(parent.kind(), FN | IF_EXPR | WHILE_EXPR | LOOP_EXPR)
+    }
+}
+
+#[test]
+fn test_literal_with_attr() {
+    let parse = ast::SourceFile::parse(r#"const _: &str = { #[attr] "Hello" };"#);
+    let lit = parse.tree().syntax().descendants().find_map(ast::Literal::cast).unwrap();
+    assert_eq!(lit.token().text(), r#""Hello""#);
+}
+
+impl ast::RecordExprField {
+    pub fn parent_record_lit(&self) -> ast::RecordExpr {
+        self.syntax().ancestors().find_map(ast::RecordExpr::cast).unwrap()
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum CallableExpr {
+    Call(ast::CallExpr),
+    MethodCall(ast::MethodCallExpr),
+}
+
+impl ast::HasAttrs for CallableExpr {}
+impl ast::HasArgList for CallableExpr {}
+
+impl AstNode for CallableExpr {
+    fn can_cast(kind: parser::SyntaxKind) -> bool
+    where
+        Self: Sized,
+    {
+        ast::CallExpr::can_cast(kind) || ast::MethodCallExpr::can_cast(kind)
+    }
+
+    fn cast(syntax: SyntaxNode) -> Option<Self>
+    where
+        Self: Sized,
+    {
+        if let Some(it) = ast::CallExpr::cast(syntax.clone()) {
+            Some(Self::Call(it))
+        } else {
+            ast::MethodCallExpr::cast(syntax).map(Self::MethodCall)
+        }
+    }
+
+    fn syntax(&self) -> &SyntaxNode {
+        match self {
+            Self::Call(it) => it.syntax(),
+            Self::MethodCall(it) => it.syntax(),
+        }
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ast/generated.rs b/src/tools/rust-analyzer/crates/syntax/src/ast/generated.rs
new file mode 100644
index 000000000..843b43cf0
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/ast/generated.rs
@@ -0,0 +1,41 @@
+//! This file is actually hand-written, but the submodules are indeed generated.
+#[rustfmt::skip]
+pub(crate) mod nodes;
+#[rustfmt::skip]
+pub(crate) mod tokens;
+
+use crate::{
+    AstNode,
+    SyntaxKind::{self, *},
+    SyntaxNode,
+};
+
+pub(crate) use nodes::*;
+
+// Stmt is the only nested enum, so it's easier to just hand-write it
+impl AstNode for Stmt {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            LET_STMT | EXPR_STMT => true,
+            _ => Item::can_cast(kind),
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        let res = match syntax.kind() {
+            LET_STMT => Stmt::LetStmt(LetStmt { syntax }),
+            EXPR_STMT => Stmt::ExprStmt(ExprStmt { syntax }),
+            _ => {
+                let item = Item::cast(syntax)?;
+                Stmt::Item(item)
+            }
+        };
+        Some(res)
+    }
+    fn syntax(&self) -> &SyntaxNode {
+        match self {
+            Stmt::LetStmt(it) => &it.syntax,
+            Stmt::ExprStmt(it) => &it.syntax,
+            Stmt::Item(it) => it.syntax(),
+        }
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ast/generated/nodes.rs b/src/tools/rust-analyzer/crates/syntax/src/ast/generated/nodes.rs
new file mode 100644
index 000000000..63309a155
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/ast/generated/nodes.rs
@@ -0,0 +1,4806 @@
+//! Generated by `sourcegen_ast`, do not edit by hand.
+
+#![allow(non_snake_case)]
+use crate::{
+    ast::{self, support, AstChildren, AstNode},
+    SyntaxKind::{self, *},
+    SyntaxNode, SyntaxToken, T,
+};
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Name {
+    pub(crate) syntax: SyntaxNode,
+}
+impl Name {
+    pub fn ident_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![ident]) }
+    pub fn self_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![self]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct NameRef {
+    pub(crate) syntax: SyntaxNode,
+}
+impl NameRef {
+    pub fn ident_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![ident]) }
+    pub fn self_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![self]) }
+    pub fn super_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![super]) }
+    pub fn crate_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![crate]) }
+    pub fn Self_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![Self]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Lifetime {
+    pub(crate) syntax: SyntaxNode,
+}
+impl Lifetime {
+    pub fn lifetime_ident_token(&self) -> Option<SyntaxToken> {
+        support::token(&self.syntax, T![lifetime_ident])
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Path {
+    pub(crate) syntax: SyntaxNode,
+}
+impl Path {
+    pub fn qualifier(&self) -> Option<Path> { support::child(&self.syntax) }
+    pub fn coloncolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![::]) }
+    pub fn segment(&self) -> Option<PathSegment> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct PathSegment {
+    pub(crate) syntax: SyntaxNode,
+}
+impl PathSegment {
+    pub fn coloncolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![::]) }
+    pub fn name_ref(&self) -> Option<NameRef> { support::child(&self.syntax) }
+    pub fn generic_arg_list(&self) -> Option<GenericArgList> { support::child(&self.syntax) }
+    pub fn param_list(&self) -> Option<ParamList> { support::child(&self.syntax) }
+    pub fn ret_type(&self) -> Option<RetType> { support::child(&self.syntax) }
+    pub fn l_angle_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![<]) }
+    pub fn path_type(&self) -> Option<PathType> { support::child(&self.syntax) }
+    pub fn as_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![as]) }
+    pub fn r_angle_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![>]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct GenericArgList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl GenericArgList {
+    pub fn coloncolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![::]) }
+    pub fn l_angle_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![<]) }
+    pub fn generic_args(&self) -> AstChildren<GenericArg> { support::children(&self.syntax) }
+    pub fn r_angle_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![>]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ParamList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ParamList {
+    pub fn l_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['(']) }
+    pub fn self_param(&self) -> Option<SelfParam> { support::child(&self.syntax) }
+    pub fn comma_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![,]) }
+    pub fn params(&self) -> AstChildren<Param> { support::children(&self.syntax) }
+    pub fn r_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![')']) }
+    pub fn pipe_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![|]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct RetType {
+    pub(crate) syntax: SyntaxNode,
+}
+impl RetType {
+    pub fn thin_arrow_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![->]) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct PathType {
+    pub(crate) syntax: SyntaxNode,
+}
+impl PathType {
+    pub fn path(&self) -> Option<Path> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct TypeArg {
+    pub(crate) syntax: SyntaxNode,
+}
+impl TypeArg {
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct AssocTypeArg {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasTypeBounds for AssocTypeArg {}
+impl AssocTypeArg {
+    pub fn name_ref(&self) -> Option<NameRef> { support::child(&self.syntax) }
+    pub fn generic_param_list(&self) -> Option<GenericParamList> { support::child(&self.syntax) }
+    pub fn eq_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![=]) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+    pub fn const_arg(&self) -> Option<ConstArg> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct LifetimeArg {
+    pub(crate) syntax: SyntaxNode,
+}
+impl LifetimeArg {
+    pub fn lifetime(&self) -> Option<Lifetime> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ConstArg {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ConstArg {
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct GenericParamList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl GenericParamList {
+    pub fn l_angle_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![<]) }
+    pub fn generic_params(&self) -> AstChildren<GenericParam> { support::children(&self.syntax) }
+    pub fn r_angle_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![>]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct TypeBoundList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl TypeBoundList {
+    pub fn bounds(&self) -> AstChildren<TypeBound> { support::children(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct MacroCall {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for MacroCall {}
+impl ast::HasDocComments for MacroCall {}
+impl MacroCall {
+    pub fn path(&self) -> Option<Path> { support::child(&self.syntax) }
+    pub fn excl_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![!]) }
+    pub fn token_tree(&self) -> Option<TokenTree> { support::child(&self.syntax) }
+    pub fn semicolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![;]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Attr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl Attr {
+    pub fn pound_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![#]) }
+    pub fn excl_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![!]) }
+    pub fn l_brack_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['[']) }
+    pub fn meta(&self) -> Option<Meta> { support::child(&self.syntax) }
+    pub fn r_brack_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![']']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct TokenTree {
+    pub(crate) syntax: SyntaxNode,
+}
+impl TokenTree {
+    pub fn l_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['(']) }
+    pub fn r_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![')']) }
+    pub fn l_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['{']) }
+    pub fn r_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['}']) }
+    pub fn l_brack_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['[']) }
+    pub fn r_brack_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![']']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct MacroItems {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasModuleItem for MacroItems {}
+impl MacroItems {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct MacroStmts {
+    pub(crate) syntax: SyntaxNode,
+}
+impl MacroStmts {
+    pub fn statements(&self) -> AstChildren<Stmt> { support::children(&self.syntax) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct SourceFile {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for SourceFile {}
+impl ast::HasModuleItem for SourceFile {}
+impl ast::HasDocComments for SourceFile {}
+impl SourceFile {
+    pub fn shebang_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![shebang]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Const {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for Const {}
+impl ast::HasName for Const {}
+impl ast::HasVisibility for Const {}
+impl ast::HasDocComments for Const {}
+impl Const {
+    pub fn default_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![default]) }
+    pub fn const_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![const]) }
+    pub fn underscore_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![_]) }
+    pub fn colon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![:]) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+    pub fn eq_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![=]) }
+    pub fn body(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn semicolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![;]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Enum {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for Enum {}
+impl ast::HasName for Enum {}
+impl ast::HasVisibility for Enum {}
+impl ast::HasGenericParams for Enum {}
+impl ast::HasDocComments for Enum {}
+impl Enum {
+    pub fn enum_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![enum]) }
+    pub fn variant_list(&self) -> Option<VariantList> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ExternBlock {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for ExternBlock {}
+impl ast::HasDocComments for ExternBlock {}
+impl ExternBlock {
+    pub fn unsafe_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![unsafe]) }
+    pub fn abi(&self) -> Option<Abi> { support::child(&self.syntax) }
+    pub fn extern_item_list(&self) -> Option<ExternItemList> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ExternCrate {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for ExternCrate {}
+impl ast::HasVisibility for ExternCrate {}
+impl ast::HasDocComments for ExternCrate {}
+impl ExternCrate {
+    pub fn extern_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![extern]) }
+    pub fn crate_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![crate]) }
+    pub fn name_ref(&self) -> Option<NameRef> { support::child(&self.syntax) }
+    pub fn rename(&self) -> Option<Rename> { support::child(&self.syntax) }
+    pub fn semicolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![;]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Fn {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for Fn {}
+impl ast::HasName for Fn {}
+impl ast::HasVisibility for Fn {}
+impl ast::HasGenericParams for Fn {}
+impl ast::HasDocComments for Fn {}
+impl Fn {
+    pub fn default_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![default]) }
+    pub fn const_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![const]) }
+    pub fn async_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![async]) }
+    pub fn unsafe_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![unsafe]) }
+    pub fn abi(&self) -> Option<Abi> { support::child(&self.syntax) }
+    pub fn fn_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![fn]) }
+    pub fn param_list(&self) -> Option<ParamList> { support::child(&self.syntax) }
+    pub fn ret_type(&self) -> Option<RetType> { support::child(&self.syntax) }
+    pub fn body(&self) -> Option<BlockExpr> { support::child(&self.syntax) }
+    pub fn semicolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![;]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Impl {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for Impl {}
+impl ast::HasVisibility for Impl {}
+impl ast::HasGenericParams for Impl {}
+impl ast::HasDocComments for Impl {}
+impl Impl {
+    pub fn default_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![default]) }
+    pub fn unsafe_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![unsafe]) }
+    pub fn impl_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![impl]) }
+    pub fn const_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![const]) }
+    pub fn excl_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![!]) }
+    pub fn for_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![for]) }
+    pub fn assoc_item_list(&self) -> Option<AssocItemList> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct MacroRules {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for MacroRules {}
+impl ast::HasName for MacroRules {}
+impl ast::HasVisibility for MacroRules {}
+impl ast::HasDocComments for MacroRules {}
+impl MacroRules {
+    pub fn macro_rules_token(&self) -> Option<SyntaxToken> {
+        support::token(&self.syntax, T![macro_rules])
+    }
+    pub fn excl_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![!]) }
+    pub fn token_tree(&self) -> Option<TokenTree> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct MacroDef {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for MacroDef {}
+impl ast::HasName for MacroDef {}
+impl ast::HasVisibility for MacroDef {}
+impl ast::HasDocComments for MacroDef {}
+impl MacroDef {
+    pub fn macro_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![macro]) }
+    pub fn args(&self) -> Option<TokenTree> { support::child(&self.syntax) }
+    pub fn body(&self) -> Option<TokenTree> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Module {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for Module {}
+impl ast::HasName for Module {}
+impl ast::HasVisibility for Module {}
+impl ast::HasDocComments for Module {}
+impl Module {
+    pub fn mod_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![mod]) }
+    pub fn item_list(&self) -> Option<ItemList> { support::child(&self.syntax) }
+    pub fn semicolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![;]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Static {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for Static {}
+impl ast::HasName for Static {}
+impl ast::HasVisibility for Static {}
+impl ast::HasDocComments for Static {}
+impl Static {
+    pub fn static_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![static]) }
+    pub fn mut_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![mut]) }
+    pub fn colon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![:]) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+    pub fn eq_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![=]) }
+    pub fn body(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn semicolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![;]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Struct {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for Struct {}
+impl ast::HasName for Struct {}
+impl ast::HasVisibility for Struct {}
+impl ast::HasGenericParams for Struct {}
+impl ast::HasDocComments for Struct {}
+impl Struct {
+    pub fn struct_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![struct]) }
+    pub fn semicolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![;]) }
+    pub fn field_list(&self) -> Option<FieldList> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Trait {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for Trait {}
+impl ast::HasName for Trait {}
+impl ast::HasVisibility for Trait {}
+impl ast::HasGenericParams for Trait {}
+impl ast::HasTypeBounds for Trait {}
+impl ast::HasDocComments for Trait {}
+impl Trait {
+    pub fn unsafe_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![unsafe]) }
+    pub fn auto_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![auto]) }
+    pub fn trait_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![trait]) }
+    pub fn assoc_item_list(&self) -> Option<AssocItemList> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct TypeAlias {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for TypeAlias {}
+impl ast::HasName for TypeAlias {}
+impl ast::HasVisibility for TypeAlias {}
+impl ast::HasGenericParams for TypeAlias {}
+impl ast::HasTypeBounds for TypeAlias {}
+impl ast::HasDocComments for TypeAlias {}
+impl TypeAlias {
+    pub fn default_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![default]) }
+    pub fn type_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![type]) }
+    pub fn eq_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![=]) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+    pub fn semicolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![;]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Union {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for Union {}
+impl ast::HasName for Union {}
+impl ast::HasVisibility for Union {}
+impl ast::HasGenericParams for Union {}
+impl ast::HasDocComments for Union {}
+impl Union {
+    pub fn union_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![union]) }
+    pub fn record_field_list(&self) -> Option<RecordFieldList> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Use {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for Use {}
+impl ast::HasVisibility for Use {}
+impl ast::HasDocComments for Use {}
+impl Use {
+    pub fn use_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![use]) }
+    pub fn use_tree(&self) -> Option<UseTree> { support::child(&self.syntax) }
+    pub fn semicolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![;]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Visibility {
+    pub(crate) syntax: SyntaxNode,
+}
+impl Visibility {
+    pub fn pub_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![pub]) }
+    pub fn l_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['(']) }
+    pub fn in_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![in]) }
+    pub fn path(&self) -> Option<Path> { support::child(&self.syntax) }
+    pub fn r_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![')']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ItemList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for ItemList {}
+impl ast::HasModuleItem for ItemList {}
+impl ItemList {
+    pub fn l_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['{']) }
+    pub fn r_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['}']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Rename {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasName for Rename {}
+impl Rename {
+    pub fn as_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![as]) }
+    pub fn underscore_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![_]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct UseTree {
+    pub(crate) syntax: SyntaxNode,
+}
+impl UseTree {
+    pub fn path(&self) -> Option<Path> { support::child(&self.syntax) }
+    pub fn coloncolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![::]) }
+    pub fn star_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![*]) }
+    pub fn use_tree_list(&self) -> Option<UseTreeList> { support::child(&self.syntax) }
+    pub fn rename(&self) -> Option<Rename> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct UseTreeList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl UseTreeList {
+    pub fn l_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['{']) }
+    pub fn use_trees(&self) -> AstChildren<UseTree> { support::children(&self.syntax) }
+    pub fn r_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['}']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Abi {
+    pub(crate) syntax: SyntaxNode,
+}
+impl Abi {
+    pub fn extern_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![extern]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct WhereClause {
+    pub(crate) syntax: SyntaxNode,
+}
+impl WhereClause {
+    pub fn where_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![where]) }
+    pub fn predicates(&self) -> AstChildren<WherePred> { support::children(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct BlockExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for BlockExpr {}
+impl BlockExpr {
+    pub fn label(&self) -> Option<Label> { support::child(&self.syntax) }
+    pub fn try_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![try]) }
+    pub fn unsafe_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![unsafe]) }
+    pub fn async_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![async]) }
+    pub fn const_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![const]) }
+    pub fn stmt_list(&self) -> Option<StmtList> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct SelfParam {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for SelfParam {}
+impl ast::HasName for SelfParam {}
+impl SelfParam {
+    pub fn amp_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![&]) }
+    pub fn lifetime(&self) -> Option<Lifetime> { support::child(&self.syntax) }
+    pub fn mut_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![mut]) }
+    pub fn colon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![:]) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Param {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for Param {}
+impl Param {
+    pub fn pat(&self) -> Option<Pat> { support::child(&self.syntax) }
+    pub fn colon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![:]) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+    pub fn dotdotdot_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![...]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct RecordFieldList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl RecordFieldList {
+    pub fn l_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['{']) }
+    pub fn fields(&self) -> AstChildren<RecordField> { support::children(&self.syntax) }
+    pub fn r_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['}']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct TupleFieldList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl TupleFieldList {
+    pub fn l_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['(']) }
+    pub fn fields(&self) -> AstChildren<TupleField> { support::children(&self.syntax) }
+    pub fn r_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![')']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct RecordField {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for RecordField {}
+impl ast::HasName for RecordField {}
+impl ast::HasVisibility for RecordField {}
+impl ast::HasDocComments for RecordField {}
+impl RecordField {
+    pub fn colon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![:]) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct TupleField {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for TupleField {}
+impl ast::HasVisibility for TupleField {}
+impl ast::HasDocComments for TupleField {}
+impl TupleField {
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct VariantList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl VariantList {
+    pub fn l_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['{']) }
+    pub fn variants(&self) -> AstChildren<Variant> { support::children(&self.syntax) }
+    pub fn r_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['}']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Variant {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for Variant {}
+impl ast::HasName for Variant {}
+impl ast::HasVisibility for Variant {}
+impl ast::HasDocComments for Variant {}
+impl Variant {
+    pub fn field_list(&self) -> Option<FieldList> { support::child(&self.syntax) }
+    pub fn eq_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![=]) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct AssocItemList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for AssocItemList {}
+impl AssocItemList {
+    pub fn l_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['{']) }
+    pub fn assoc_items(&self) -> AstChildren<AssocItem> { support::children(&self.syntax) }
+    pub fn r_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['}']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ExternItemList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for ExternItemList {}
+impl ExternItemList {
+    pub fn l_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['{']) }
+    pub fn extern_items(&self) -> AstChildren<ExternItem> { support::children(&self.syntax) }
+    pub fn r_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['}']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ConstParam {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for ConstParam {}
+impl ast::HasName for ConstParam {}
+impl ConstParam {
+    pub fn const_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![const]) }
+    pub fn colon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![:]) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+    pub fn eq_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![=]) }
+    pub fn default_val(&self) -> Option<Expr> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct LifetimeParam {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for LifetimeParam {}
+impl ast::HasTypeBounds for LifetimeParam {}
+impl LifetimeParam {
+    pub fn lifetime(&self) -> Option<Lifetime> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct TypeParam {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for TypeParam {}
+impl ast::HasName for TypeParam {}
+impl ast::HasTypeBounds for TypeParam {}
+impl TypeParam {
+    pub fn eq_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![=]) }
+    pub fn default_type(&self) -> Option<Type> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct WherePred {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasTypeBounds for WherePred {}
+impl WherePred {
+    pub fn for_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![for]) }
+    pub fn generic_param_list(&self) -> Option<GenericParamList> { support::child(&self.syntax) }
+    pub fn lifetime(&self) -> Option<Lifetime> { support::child(&self.syntax) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Meta {
+    pub(crate) syntax: SyntaxNode,
+}
+impl Meta {
+    pub fn path(&self) -> Option<Path> { support::child(&self.syntax) }
+    pub fn eq_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![=]) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn token_tree(&self) -> Option<TokenTree> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ExprStmt {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ExprStmt {
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn semicolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![;]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct LetStmt {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for LetStmt {}
+impl LetStmt {
+    pub fn let_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![let]) }
+    pub fn pat(&self) -> Option<Pat> { support::child(&self.syntax) }
+    pub fn colon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![:]) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+    pub fn eq_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![=]) }
+    pub fn initializer(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn let_else(&self) -> Option<LetElse> { support::child(&self.syntax) }
+    pub fn semicolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![;]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct LetElse {
+    pub(crate) syntax: SyntaxNode,
+}
+impl LetElse {
+    pub fn else_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![else]) }
+    pub fn block_expr(&self) -> Option<BlockExpr> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ArrayExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for ArrayExpr {}
+impl ArrayExpr {
+    pub fn l_brack_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['[']) }
+    pub fn exprs(&self) -> AstChildren<Expr> { support::children(&self.syntax) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn semicolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![;]) }
+    pub fn r_brack_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![']']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct AwaitExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for AwaitExpr {}
+impl AwaitExpr {
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn dot_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![.]) }
+    pub fn await_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![await]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct BinExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for BinExpr {}
+impl BinExpr {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct BoxExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for BoxExpr {}
+impl BoxExpr {
+    pub fn box_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![box]) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct BreakExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for BreakExpr {}
+impl BreakExpr {
+    pub fn break_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![break]) }
+    pub fn lifetime(&self) -> Option<Lifetime> { support::child(&self.syntax) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct CallExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for CallExpr {}
+impl ast::HasArgList for CallExpr {}
+impl CallExpr {
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct CastExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for CastExpr {}
+impl CastExpr {
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn as_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![as]) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ClosureExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for ClosureExpr {}
+impl ClosureExpr {
+    pub fn for_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![for]) }
+    pub fn generic_param_list(&self) -> Option<GenericParamList> { support::child(&self.syntax) }
+    pub fn static_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![static]) }
+    pub fn async_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![async]) }
+    pub fn move_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![move]) }
+    pub fn param_list(&self) -> Option<ParamList> { support::child(&self.syntax) }
+    pub fn ret_type(&self) -> Option<RetType> { support::child(&self.syntax) }
+    pub fn body(&self) -> Option<Expr> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ContinueExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for ContinueExpr {}
+impl ContinueExpr {
+    pub fn continue_token(&self) -> Option<SyntaxToken> {
+        support::token(&self.syntax, T![continue])
+    }
+    pub fn lifetime(&self) -> Option<Lifetime> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct FieldExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for FieldExpr {}
+impl FieldExpr {
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn dot_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![.]) }
+    pub fn name_ref(&self) -> Option<NameRef> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ForExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for ForExpr {}
+impl ForExpr {
+    pub fn for_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![for]) }
+    pub fn pat(&self) -> Option<Pat> { support::child(&self.syntax) }
+    pub fn in_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![in]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct IfExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for IfExpr {}
+impl IfExpr {
+    pub fn if_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![if]) }
+    pub fn else_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![else]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct IndexExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for IndexExpr {}
+impl IndexExpr {
+    pub fn l_brack_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['[']) }
+    pub fn r_brack_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![']']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Literal {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for Literal {}
+impl Literal {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct LoopExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for LoopExpr {}
+impl ast::HasLoopBody for LoopExpr {}
+impl LoopExpr {
+    pub fn loop_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![loop]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct MacroExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl MacroExpr {
+    pub fn macro_call(&self) -> Option<MacroCall> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct MatchExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for MatchExpr {}
+impl MatchExpr {
+    pub fn match_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![match]) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn match_arm_list(&self) -> Option<MatchArmList> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct MethodCallExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for MethodCallExpr {}
+impl ast::HasArgList for MethodCallExpr {}
+impl MethodCallExpr {
+    pub fn receiver(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn dot_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![.]) }
+    pub fn name_ref(&self) -> Option<NameRef> { support::child(&self.syntax) }
+    pub fn generic_arg_list(&self) -> Option<GenericArgList> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ParenExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for ParenExpr {}
+impl ParenExpr {
+    pub fn l_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['(']) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn r_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![')']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct PathExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for PathExpr {}
+impl PathExpr {
+    pub fn path(&self) -> Option<Path> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct PrefixExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for PrefixExpr {}
+impl PrefixExpr {
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct RangeExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for RangeExpr {}
+impl RangeExpr {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct RecordExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl RecordExpr {
+    pub fn path(&self) -> Option<Path> { support::child(&self.syntax) }
+    pub fn record_expr_field_list(&self) -> Option<RecordExprFieldList> {
+        support::child(&self.syntax)
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct RefExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for RefExpr {}
+impl RefExpr {
+    pub fn amp_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![&]) }
+    pub fn raw_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![raw]) }
+    pub fn mut_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![mut]) }
+    pub fn const_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![const]) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ReturnExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for ReturnExpr {}
+impl ReturnExpr {
+    pub fn return_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![return]) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct TryExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for TryExpr {}
+impl TryExpr {
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn question_mark_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![?]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct TupleExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for TupleExpr {}
+impl TupleExpr {
+    pub fn l_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['(']) }
+    pub fn fields(&self) -> AstChildren<Expr> { support::children(&self.syntax) }
+    pub fn r_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![')']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct WhileExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for WhileExpr {}
+impl WhileExpr {
+    pub fn while_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![while]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct YieldExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for YieldExpr {}
+impl YieldExpr {
+    pub fn yield_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![yield]) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct LetExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for LetExpr {}
+impl LetExpr {
+    pub fn let_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![let]) }
+    pub fn pat(&self) -> Option<Pat> { support::child(&self.syntax) }
+    pub fn eq_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![=]) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct UnderscoreExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for UnderscoreExpr {}
+impl UnderscoreExpr {
+    pub fn underscore_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![_]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct StmtList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for StmtList {}
+impl StmtList {
+    pub fn l_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['{']) }
+    pub fn statements(&self) -> AstChildren<Stmt> { support::children(&self.syntax) }
+    pub fn tail_expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn r_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['}']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Label {
+    pub(crate) syntax: SyntaxNode,
+}
+impl Label {
+    pub fn lifetime(&self) -> Option<Lifetime> { support::child(&self.syntax) }
+    pub fn colon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![:]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct RecordExprFieldList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for RecordExprFieldList {}
+impl RecordExprFieldList {
+    pub fn l_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['{']) }
+    pub fn fields(&self) -> AstChildren<RecordExprField> { support::children(&self.syntax) }
+    pub fn dotdot_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![..]) }
+    pub fn spread(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn r_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['}']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct RecordExprField {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for RecordExprField {}
+impl RecordExprField {
+    pub fn name_ref(&self) -> Option<NameRef> { support::child(&self.syntax) }
+    pub fn colon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![:]) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ArgList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ArgList {
+    pub fn l_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['(']) }
+    pub fn args(&self) -> AstChildren<Expr> { support::children(&self.syntax) }
+    pub fn r_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![')']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct MatchArmList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for MatchArmList {}
+impl MatchArmList {
+    pub fn l_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['{']) }
+    pub fn arms(&self) -> AstChildren<MatchArm> { support::children(&self.syntax) }
+    pub fn r_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['}']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct MatchArm {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for MatchArm {}
+impl MatchArm {
+    pub fn pat(&self) -> Option<Pat> { support::child(&self.syntax) }
+    pub fn guard(&self) -> Option<MatchGuard> { support::child(&self.syntax) }
+    pub fn fat_arrow_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![=>]) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn comma_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![,]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct MatchGuard {
+    pub(crate) syntax: SyntaxNode,
+}
+impl MatchGuard {
+    pub fn if_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![if]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ArrayType {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ArrayType {
+    pub fn l_brack_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['[']) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+    pub fn semicolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![;]) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn r_brack_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![']']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct DynTraitType {
+    pub(crate) syntax: SyntaxNode,
+}
+impl DynTraitType {
+    pub fn dyn_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![dyn]) }
+    pub fn type_bound_list(&self) -> Option<TypeBoundList> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct FnPtrType {
+    pub(crate) syntax: SyntaxNode,
+}
+impl FnPtrType {
+    pub fn const_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![const]) }
+    pub fn async_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![async]) }
+    pub fn unsafe_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![unsafe]) }
+    pub fn abi(&self) -> Option<Abi> { support::child(&self.syntax) }
+    pub fn fn_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![fn]) }
+    pub fn param_list(&self) -> Option<ParamList> { support::child(&self.syntax) }
+    pub fn ret_type(&self) -> Option<RetType> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ForType {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ForType {
+    pub fn for_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![for]) }
+    pub fn generic_param_list(&self) -> Option<GenericParamList> { support::child(&self.syntax) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ImplTraitType {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ImplTraitType {
+    pub fn impl_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![impl]) }
+    pub fn type_bound_list(&self) -> Option<TypeBoundList> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct InferType {
+    pub(crate) syntax: SyntaxNode,
+}
+impl InferType {
+    pub fn underscore_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![_]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct MacroType {
+    pub(crate) syntax: SyntaxNode,
+}
+impl MacroType {
+    pub fn macro_call(&self) -> Option<MacroCall> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct NeverType {
+    pub(crate) syntax: SyntaxNode,
+}
+impl NeverType {
+    pub fn excl_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![!]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ParenType {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ParenType {
+    pub fn l_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['(']) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+    pub fn r_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![')']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct PtrType {
+    pub(crate) syntax: SyntaxNode,
+}
+impl PtrType {
+    pub fn star_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![*]) }
+    pub fn const_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![const]) }
+    pub fn mut_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![mut]) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct RefType {
+    pub(crate) syntax: SyntaxNode,
+}
+impl RefType {
+    pub fn amp_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![&]) }
+    pub fn lifetime(&self) -> Option<Lifetime> { support::child(&self.syntax) }
+    pub fn mut_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![mut]) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct SliceType {
+    pub(crate) syntax: SyntaxNode,
+}
+impl SliceType {
+    pub fn l_brack_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['[']) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+    pub fn r_brack_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![']']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct TupleType {
+    pub(crate) syntax: SyntaxNode,
+}
+impl TupleType {
+    pub fn l_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['(']) }
+    pub fn fields(&self) -> AstChildren<Type> { support::children(&self.syntax) }
+    pub fn r_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![')']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct TypeBound {
+    pub(crate) syntax: SyntaxNode,
+}
+impl TypeBound {
+    pub fn lifetime(&self) -> Option<Lifetime> { support::child(&self.syntax) }
+    pub fn question_mark_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![?]) }
+    pub fn tilde_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![~]) }
+    pub fn const_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![const]) }
+    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct IdentPat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for IdentPat {}
+impl ast::HasName for IdentPat {}
+impl IdentPat {
+    pub fn ref_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![ref]) }
+    pub fn mut_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![mut]) }
+    pub fn at_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![@]) }
+    pub fn pat(&self) -> Option<Pat> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct BoxPat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl BoxPat {
+    pub fn box_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![box]) }
+    pub fn pat(&self) -> Option<Pat> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct RestPat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for RestPat {}
+impl RestPat {
+    pub fn dotdot_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![..]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct LiteralPat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl LiteralPat {
+    pub fn literal(&self) -> Option<Literal> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct MacroPat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl MacroPat {
+    pub fn macro_call(&self) -> Option<MacroCall> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct OrPat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl OrPat {
+    pub fn pats(&self) -> AstChildren<Pat> { support::children(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ParenPat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ParenPat {
+    pub fn l_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['(']) }
+    pub fn pat(&self) -> Option<Pat> { support::child(&self.syntax) }
+    pub fn r_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![')']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct PathPat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl PathPat {
+    pub fn path(&self) -> Option<Path> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct WildcardPat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl WildcardPat {
+    pub fn underscore_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![_]) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct RangePat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl RangePat {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct RecordPat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl RecordPat {
+    pub fn path(&self) -> Option<Path> { support::child(&self.syntax) }
+    pub fn record_pat_field_list(&self) -> Option<RecordPatFieldList> {
+        support::child(&self.syntax)
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct RefPat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl RefPat {
+    pub fn amp_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![&]) }
+    pub fn mut_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![mut]) }
+    pub fn pat(&self) -> Option<Pat> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct SlicePat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl SlicePat {
+    pub fn l_brack_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['[']) }
+    pub fn pats(&self) -> AstChildren<Pat> { support::children(&self.syntax) }
+    pub fn r_brack_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![']']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct TuplePat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl TuplePat {
+    pub fn l_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['(']) }
+    pub fn fields(&self) -> AstChildren<Pat> { support::children(&self.syntax) }
+    pub fn r_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![')']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct TupleStructPat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl TupleStructPat {
+    pub fn path(&self) -> Option<Path> { support::child(&self.syntax) }
+    pub fn l_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['(']) }
+    pub fn fields(&self) -> AstChildren<Pat> { support::children(&self.syntax) }
+    pub fn r_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![')']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ConstBlockPat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ConstBlockPat {
+    pub fn const_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![const]) }
+    pub fn block_expr(&self) -> Option<BlockExpr> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct RecordPatFieldList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl RecordPatFieldList {
+    pub fn l_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['{']) }
+    pub fn fields(&self) -> AstChildren<RecordPatField> { support::children(&self.syntax) }
+    pub fn rest_pat(&self) -> Option<RestPat> { support::child(&self.syntax) }
+    pub fn r_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['}']) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct RecordPatField {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for RecordPatField {}
+impl RecordPatField {
+    pub fn name_ref(&self) -> Option<NameRef> { support::child(&self.syntax) }
+    pub fn colon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![:]) }
+    pub fn pat(&self) -> Option<Pat> { support::child(&self.syntax) }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum GenericArg {
+    TypeArg(TypeArg),
+    AssocTypeArg(AssocTypeArg),
+    LifetimeArg(LifetimeArg),
+    ConstArg(ConstArg),
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum Type {
+    ArrayType(ArrayType),
+    DynTraitType(DynTraitType),
+    FnPtrType(FnPtrType),
+    ForType(ForType),
+    ImplTraitType(ImplTraitType),
+    InferType(InferType),
+    MacroType(MacroType),
+    NeverType(NeverType),
+    ParenType(ParenType),
+    PathType(PathType),
+    PtrType(PtrType),
+    RefType(RefType),
+    SliceType(SliceType),
+    TupleType(TupleType),
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum Expr {
+    ArrayExpr(ArrayExpr),
+    AwaitExpr(AwaitExpr),
+    BinExpr(BinExpr),
+    BlockExpr(BlockExpr),
+    BoxExpr(BoxExpr),
+    BreakExpr(BreakExpr),
+    CallExpr(CallExpr),
+    CastExpr(CastExpr),
+    ClosureExpr(ClosureExpr),
+    ContinueExpr(ContinueExpr),
+    FieldExpr(FieldExpr),
+    ForExpr(ForExpr),
+    IfExpr(IfExpr),
+    IndexExpr(IndexExpr),
+    Literal(Literal),
+    LoopExpr(LoopExpr),
+    MacroExpr(MacroExpr),
+    MacroStmts(MacroStmts),
+    MatchExpr(MatchExpr),
+    MethodCallExpr(MethodCallExpr),
+    ParenExpr(ParenExpr),
+    PathExpr(PathExpr),
+    PrefixExpr(PrefixExpr),
+    RangeExpr(RangeExpr),
+    RecordExpr(RecordExpr),
+    RefExpr(RefExpr),
+    ReturnExpr(ReturnExpr),
+    TryExpr(TryExpr),
+    TupleExpr(TupleExpr),
+    WhileExpr(WhileExpr),
+    YieldExpr(YieldExpr),
+    LetExpr(LetExpr),
+    UnderscoreExpr(UnderscoreExpr),
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum Item {
+    Const(Const),
+    Enum(Enum),
+    ExternBlock(ExternBlock),
+    ExternCrate(ExternCrate),
+    Fn(Fn),
+    Impl(Impl),
+    MacroCall(MacroCall),
+    MacroRules(MacroRules),
+    MacroDef(MacroDef),
+    Module(Module),
+    Static(Static),
+    Struct(Struct),
+    Trait(Trait),
+    TypeAlias(TypeAlias),
+    Union(Union),
+    Use(Use),
+}
+impl ast::HasAttrs for Item {}
+impl ast::HasDocComments for Item {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum Stmt {
+    ExprStmt(ExprStmt),
+    Item(Item),
+    LetStmt(LetStmt),
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum Pat {
+    IdentPat(IdentPat),
+    BoxPat(BoxPat),
+    RestPat(RestPat),
+    LiteralPat(LiteralPat),
+    MacroPat(MacroPat),
+    OrPat(OrPat),
+    ParenPat(ParenPat),
+    PathPat(PathPat),
+    WildcardPat(WildcardPat),
+    RangePat(RangePat),
+    RecordPat(RecordPat),
+    RefPat(RefPat),
+    SlicePat(SlicePat),
+    TuplePat(TuplePat),
+    TupleStructPat(TupleStructPat),
+    ConstBlockPat(ConstBlockPat),
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum FieldList {
+    RecordFieldList(RecordFieldList),
+    TupleFieldList(TupleFieldList),
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum Adt {
+    Enum(Enum),
+    Struct(Struct),
+    Union(Union),
+}
+impl ast::HasAttrs for Adt {}
+impl ast::HasDocComments for Adt {}
+impl ast::HasGenericParams for Adt {}
+impl ast::HasName for Adt {}
+impl ast::HasVisibility for Adt {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum AssocItem {
+    Const(Const),
+    Fn(Fn),
+    MacroCall(MacroCall),
+    TypeAlias(TypeAlias),
+}
+impl ast::HasAttrs for AssocItem {}
+impl ast::HasDocComments for AssocItem {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum ExternItem {
+    Fn(Fn),
+    MacroCall(MacroCall),
+    Static(Static),
+    TypeAlias(TypeAlias),
+}
+impl ast::HasAttrs for ExternItem {}
+impl ast::HasDocComments for ExternItem {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum GenericParam {
+    ConstParam(ConstParam),
+    LifetimeParam(LifetimeParam),
+    TypeParam(TypeParam),
+}
+impl ast::HasAttrs for GenericParam {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct AnyHasArgList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasArgList for AnyHasArgList {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct AnyHasAttrs {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasAttrs for AnyHasAttrs {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct AnyHasDocComments {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasDocComments for AnyHasDocComments {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct AnyHasGenericParams {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasGenericParams for AnyHasGenericParams {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct AnyHasLoopBody {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasLoopBody for AnyHasLoopBody {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct AnyHasModuleItem {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasModuleItem for AnyHasModuleItem {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct AnyHasName {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasName for AnyHasName {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct AnyHasTypeBounds {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasTypeBounds for AnyHasTypeBounds {}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct AnyHasVisibility {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::HasVisibility for AnyHasVisibility {}
+impl AstNode for Name {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == NAME }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for NameRef {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == NAME_REF }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Lifetime {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == LIFETIME }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Path {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == PATH }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for PathSegment {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == PATH_SEGMENT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for GenericArgList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == GENERIC_ARG_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ParamList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == PARAM_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for RetType {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == RET_TYPE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for PathType {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == PATH_TYPE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for TypeArg {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == TYPE_ARG }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for AssocTypeArg {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == ASSOC_TYPE_ARG }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for LifetimeArg {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == LIFETIME_ARG }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ConstArg {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == CONST_ARG }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for GenericParamList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == GENERIC_PARAM_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for TypeBoundList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == TYPE_BOUND_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for MacroCall {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == MACRO_CALL }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Attr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == ATTR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for TokenTree {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == TOKEN_TREE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for MacroItems {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == MACRO_ITEMS }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for MacroStmts {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == MACRO_STMTS }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for SourceFile {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == SOURCE_FILE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Const {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == CONST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Enum {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == ENUM }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ExternBlock {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == EXTERN_BLOCK }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ExternCrate {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == EXTERN_CRATE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Fn {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == FN }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Impl {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == IMPL }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for MacroRules {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == MACRO_RULES }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for MacroDef {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == MACRO_DEF }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Module {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == MODULE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Static {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == STATIC }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Struct {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == STRUCT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Trait {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == TRAIT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for TypeAlias {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == TYPE_ALIAS }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Union {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == UNION }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Use {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == USE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Visibility {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == VISIBILITY }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ItemList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == ITEM_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Rename {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == RENAME }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for UseTree {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == USE_TREE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for UseTreeList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == USE_TREE_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Abi {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == ABI }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for WhereClause {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == WHERE_CLAUSE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for BlockExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == BLOCK_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for SelfParam {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == SELF_PARAM }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Param {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == PARAM }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for RecordFieldList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == RECORD_FIELD_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for TupleFieldList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == TUPLE_FIELD_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for RecordField {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == RECORD_FIELD }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for TupleField {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == TUPLE_FIELD }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for VariantList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == VARIANT_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Variant {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == VARIANT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for AssocItemList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == ASSOC_ITEM_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ExternItemList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == EXTERN_ITEM_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ConstParam {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == CONST_PARAM }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for LifetimeParam {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == LIFETIME_PARAM }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for TypeParam {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == TYPE_PARAM }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for WherePred {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == WHERE_PRED }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Meta {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == META }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ExprStmt {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == EXPR_STMT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for LetStmt {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == LET_STMT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for LetElse {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == LET_ELSE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ArrayExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == ARRAY_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for AwaitExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == AWAIT_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for BinExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == BIN_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for BoxExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == BOX_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for BreakExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == BREAK_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for CallExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == CALL_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for CastExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == CAST_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ClosureExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == CLOSURE_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ContinueExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == CONTINUE_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for FieldExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == FIELD_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ForExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == FOR_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for IfExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == IF_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for IndexExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == INDEX_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Literal {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == LITERAL }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for LoopExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == LOOP_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for MacroExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == MACRO_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for MatchExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == MATCH_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for MethodCallExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == METHOD_CALL_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ParenExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == PAREN_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for PathExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == PATH_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for PrefixExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == PREFIX_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for RangeExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == RANGE_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for RecordExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == RECORD_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for RefExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == REF_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ReturnExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == RETURN_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for TryExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == TRY_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for TupleExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == TUPLE_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for WhileExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == WHILE_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for YieldExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == YIELD_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for LetExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == LET_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for UnderscoreExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == UNDERSCORE_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for StmtList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == STMT_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for Label {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == LABEL }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for RecordExprFieldList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == RECORD_EXPR_FIELD_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for RecordExprField {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == RECORD_EXPR_FIELD }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ArgList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == ARG_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for MatchArmList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == MATCH_ARM_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for MatchArm {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == MATCH_ARM }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for MatchGuard {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == MATCH_GUARD }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ArrayType {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == ARRAY_TYPE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for DynTraitType {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == DYN_TRAIT_TYPE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for FnPtrType {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == FN_PTR_TYPE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ForType {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == FOR_TYPE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ImplTraitType {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == IMPL_TRAIT_TYPE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for InferType {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == INFER_TYPE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for MacroType {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == MACRO_TYPE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for NeverType {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == NEVER_TYPE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ParenType {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == PAREN_TYPE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for PtrType {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == PTR_TYPE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for RefType {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == REF_TYPE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for SliceType {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == SLICE_TYPE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for TupleType {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == TUPLE_TYPE }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for TypeBound {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == TYPE_BOUND }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for IdentPat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == IDENT_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for BoxPat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == BOX_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for RestPat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == REST_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for LiteralPat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == LITERAL_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for MacroPat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == MACRO_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for OrPat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == OR_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ParenPat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == PAREN_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for PathPat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == PATH_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for WildcardPat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == WILDCARD_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for RangePat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == RANGE_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for RecordPat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == RECORD_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for RefPat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == REF_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for SlicePat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == SLICE_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for TuplePat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == TUPLE_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for TupleStructPat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == TUPLE_STRUCT_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for ConstBlockPat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == CONST_BLOCK_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for RecordPatFieldList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == RECORD_PAT_FIELD_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AstNode for RecordPatField {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == RECORD_PAT_FIELD }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl From<TypeArg> for GenericArg {
+    fn from(node: TypeArg) -> GenericArg { GenericArg::TypeArg(node) }
+}
+impl From<AssocTypeArg> for GenericArg {
+    fn from(node: AssocTypeArg) -> GenericArg { GenericArg::AssocTypeArg(node) }
+}
+impl From<LifetimeArg> for GenericArg {
+    fn from(node: LifetimeArg) -> GenericArg { GenericArg::LifetimeArg(node) }
+}
+impl From<ConstArg> for GenericArg {
+    fn from(node: ConstArg) -> GenericArg { GenericArg::ConstArg(node) }
+}
+impl AstNode for GenericArg {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            TYPE_ARG | ASSOC_TYPE_ARG | LIFETIME_ARG | CONST_ARG => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        let res = match syntax.kind() {
+            TYPE_ARG => GenericArg::TypeArg(TypeArg { syntax }),
+            ASSOC_TYPE_ARG => GenericArg::AssocTypeArg(AssocTypeArg { syntax }),
+            LIFETIME_ARG => GenericArg::LifetimeArg(LifetimeArg { syntax }),
+            CONST_ARG => GenericArg::ConstArg(ConstArg { syntax }),
+            _ => return None,
+        };
+        Some(res)
+    }
+    fn syntax(&self) -> &SyntaxNode {
+        match self {
+            GenericArg::TypeArg(it) => &it.syntax,
+            GenericArg::AssocTypeArg(it) => &it.syntax,
+            GenericArg::LifetimeArg(it) => &it.syntax,
+            GenericArg::ConstArg(it) => &it.syntax,
+        }
+    }
+}
+impl From<ArrayType> for Type {
+    fn from(node: ArrayType) -> Type { Type::ArrayType(node) }
+}
+impl From<DynTraitType> for Type {
+    fn from(node: DynTraitType) -> Type { Type::DynTraitType(node) }
+}
+impl From<FnPtrType> for Type {
+    fn from(node: FnPtrType) -> Type { Type::FnPtrType(node) }
+}
+impl From<ForType> for Type {
+    fn from(node: ForType) -> Type { Type::ForType(node) }
+}
+impl From<ImplTraitType> for Type {
+    fn from(node: ImplTraitType) -> Type { Type::ImplTraitType(node) }
+}
+impl From<InferType> for Type {
+    fn from(node: InferType) -> Type { Type::InferType(node) }
+}
+impl From<MacroType> for Type {
+    fn from(node: MacroType) -> Type { Type::MacroType(node) }
+}
+impl From<NeverType> for Type {
+    fn from(node: NeverType) -> Type { Type::NeverType(node) }
+}
+impl From<ParenType> for Type {
+    fn from(node: ParenType) -> Type { Type::ParenType(node) }
+}
+impl From<PathType> for Type {
+    fn from(node: PathType) -> Type { Type::PathType(node) }
+}
+impl From<PtrType> for Type {
+    fn from(node: PtrType) -> Type { Type::PtrType(node) }
+}
+impl From<RefType> for Type {
+    fn from(node: RefType) -> Type { Type::RefType(node) }
+}
+impl From<SliceType> for Type {
+    fn from(node: SliceType) -> Type { Type::SliceType(node) }
+}
+impl From<TupleType> for Type {
+    fn from(node: TupleType) -> Type { Type::TupleType(node) }
+}
+impl AstNode for Type {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            ARRAY_TYPE | DYN_TRAIT_TYPE | FN_PTR_TYPE | FOR_TYPE | IMPL_TRAIT_TYPE | INFER_TYPE
+            | MACRO_TYPE | NEVER_TYPE | PAREN_TYPE | PATH_TYPE | PTR_TYPE | REF_TYPE
+            | SLICE_TYPE | TUPLE_TYPE => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        let res = match syntax.kind() {
+            ARRAY_TYPE => Type::ArrayType(ArrayType { syntax }),
+            DYN_TRAIT_TYPE => Type::DynTraitType(DynTraitType { syntax }),
+            FN_PTR_TYPE => Type::FnPtrType(FnPtrType { syntax }),
+            FOR_TYPE => Type::ForType(ForType { syntax }),
+            IMPL_TRAIT_TYPE => Type::ImplTraitType(ImplTraitType { syntax }),
+            INFER_TYPE => Type::InferType(InferType { syntax }),
+            MACRO_TYPE => Type::MacroType(MacroType { syntax }),
+            NEVER_TYPE => Type::NeverType(NeverType { syntax }),
+            PAREN_TYPE => Type::ParenType(ParenType { syntax }),
+            PATH_TYPE => Type::PathType(PathType { syntax }),
+            PTR_TYPE => Type::PtrType(PtrType { syntax }),
+            REF_TYPE => Type::RefType(RefType { syntax }),
+            SLICE_TYPE => Type::SliceType(SliceType { syntax }),
+            TUPLE_TYPE => Type::TupleType(TupleType { syntax }),
+            _ => return None,
+        };
+        Some(res)
+    }
+    fn syntax(&self) -> &SyntaxNode {
+        match self {
+            Type::ArrayType(it) => &it.syntax,
+            Type::DynTraitType(it) => &it.syntax,
+            Type::FnPtrType(it) => &it.syntax,
+            Type::ForType(it) => &it.syntax,
+            Type::ImplTraitType(it) => &it.syntax,
+            Type::InferType(it) => &it.syntax,
+            Type::MacroType(it) => &it.syntax,
+            Type::NeverType(it) => &it.syntax,
+            Type::ParenType(it) => &it.syntax,
+            Type::PathType(it) => &it.syntax,
+            Type::PtrType(it) => &it.syntax,
+            Type::RefType(it) => &it.syntax,
+            Type::SliceType(it) => &it.syntax,
+            Type::TupleType(it) => &it.syntax,
+        }
+    }
+}
+impl From<ArrayExpr> for Expr {
+    fn from(node: ArrayExpr) -> Expr { Expr::ArrayExpr(node) }
+}
+impl From<AwaitExpr> for Expr {
+    fn from(node: AwaitExpr) -> Expr { Expr::AwaitExpr(node) }
+}
+impl From<BinExpr> for Expr {
+    fn from(node: BinExpr) -> Expr { Expr::BinExpr(node) }
+}
+impl From<BlockExpr> for Expr {
+    fn from(node: BlockExpr) -> Expr { Expr::BlockExpr(node) }
+}
+impl From<BoxExpr> for Expr {
+    fn from(node: BoxExpr) -> Expr { Expr::BoxExpr(node) }
+}
+impl From<BreakExpr> for Expr {
+    fn from(node: BreakExpr) -> Expr { Expr::BreakExpr(node) }
+}
+impl From<CallExpr> for Expr {
+    fn from(node: CallExpr) -> Expr { Expr::CallExpr(node) }
+}
+impl From<CastExpr> for Expr {
+    fn from(node: CastExpr) -> Expr { Expr::CastExpr(node) }
+}
+impl From<ClosureExpr> for Expr {
+    fn from(node: ClosureExpr) -> Expr { Expr::ClosureExpr(node) }
+}
+impl From<ContinueExpr> for Expr {
+    fn from(node: ContinueExpr) -> Expr { Expr::ContinueExpr(node) }
+}
+impl From<FieldExpr> for Expr {
+    fn from(node: FieldExpr) -> Expr { Expr::FieldExpr(node) }
+}
+impl From<ForExpr> for Expr {
+    fn from(node: ForExpr) -> Expr { Expr::ForExpr(node) }
+}
+impl From<IfExpr> for Expr {
+    fn from(node: IfExpr) -> Expr { Expr::IfExpr(node) }
+}
+impl From<IndexExpr> for Expr {
+    fn from(node: IndexExpr) -> Expr { Expr::IndexExpr(node) }
+}
+impl From<Literal> for Expr {
+    fn from(node: Literal) -> Expr { Expr::Literal(node) }
+}
+impl From<LoopExpr> for Expr {
+    fn from(node: LoopExpr) -> Expr { Expr::LoopExpr(node) }
+}
+impl From<MacroExpr> for Expr {
+    fn from(node: MacroExpr) -> Expr { Expr::MacroExpr(node) }
+}
+impl From<MacroStmts> for Expr {
+    fn from(node: MacroStmts) -> Expr { Expr::MacroStmts(node) }
+}
+impl From<MatchExpr> for Expr {
+    fn from(node: MatchExpr) -> Expr { Expr::MatchExpr(node) }
+}
+impl From<MethodCallExpr> for Expr {
+    fn from(node: MethodCallExpr) -> Expr { Expr::MethodCallExpr(node) }
+}
+impl From<ParenExpr> for Expr {
+    fn from(node: ParenExpr) -> Expr { Expr::ParenExpr(node) }
+}
+impl From<PathExpr> for Expr {
+    fn from(node: PathExpr) -> Expr { Expr::PathExpr(node) }
+}
+impl From<PrefixExpr> for Expr {
+    fn from(node: PrefixExpr) -> Expr { Expr::PrefixExpr(node) }
+}
+impl From<RangeExpr> for Expr {
+    fn from(node: RangeExpr) -> Expr { Expr::RangeExpr(node) }
+}
+impl From<RecordExpr> for Expr {
+    fn from(node: RecordExpr) -> Expr { Expr::RecordExpr(node) }
+}
+impl From<RefExpr> for Expr {
+    fn from(node: RefExpr) -> Expr { Expr::RefExpr(node) }
+}
+impl From<ReturnExpr> for Expr {
+    fn from(node: ReturnExpr) -> Expr { Expr::ReturnExpr(node) }
+}
+impl From<TryExpr> for Expr {
+    fn from(node: TryExpr) -> Expr { Expr::TryExpr(node) }
+}
+impl From<TupleExpr> for Expr {
+    fn from(node: TupleExpr) -> Expr { Expr::TupleExpr(node) }
+}
+impl From<WhileExpr> for Expr {
+    fn from(node: WhileExpr) -> Expr { Expr::WhileExpr(node) }
+}
+impl From<YieldExpr> for Expr {
+    fn from(node: YieldExpr) -> Expr { Expr::YieldExpr(node) }
+}
+impl From<LetExpr> for Expr {
+    fn from(node: LetExpr) -> Expr { Expr::LetExpr(node) }
+}
+impl From<UnderscoreExpr> for Expr {
+    fn from(node: UnderscoreExpr) -> Expr { Expr::UnderscoreExpr(node) }
+}
+impl AstNode for Expr {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            ARRAY_EXPR | AWAIT_EXPR | BIN_EXPR | BLOCK_EXPR | BOX_EXPR | BREAK_EXPR | CALL_EXPR
+            | CAST_EXPR | CLOSURE_EXPR | CONTINUE_EXPR | FIELD_EXPR | FOR_EXPR | IF_EXPR
+            | INDEX_EXPR | LITERAL | LOOP_EXPR | MACRO_EXPR | MACRO_STMTS | MATCH_EXPR
+            | METHOD_CALL_EXPR | PAREN_EXPR | PATH_EXPR | PREFIX_EXPR | RANGE_EXPR
+            | RECORD_EXPR | REF_EXPR | RETURN_EXPR | TRY_EXPR | TUPLE_EXPR | WHILE_EXPR
+            | YIELD_EXPR | LET_EXPR | UNDERSCORE_EXPR => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        let res = match syntax.kind() {
+            ARRAY_EXPR => Expr::ArrayExpr(ArrayExpr { syntax }),
+            AWAIT_EXPR => Expr::AwaitExpr(AwaitExpr { syntax }),
+            BIN_EXPR => Expr::BinExpr(BinExpr { syntax }),
+            BLOCK_EXPR => Expr::BlockExpr(BlockExpr { syntax }),
+            BOX_EXPR => Expr::BoxExpr(BoxExpr { syntax }),
+            BREAK_EXPR => Expr::BreakExpr(BreakExpr { syntax }),
+            CALL_EXPR => Expr::CallExpr(CallExpr { syntax }),
+            CAST_EXPR => Expr::CastExpr(CastExpr { syntax }),
+            CLOSURE_EXPR => Expr::ClosureExpr(ClosureExpr { syntax }),
+            CONTINUE_EXPR => Expr::ContinueExpr(ContinueExpr { syntax }),
+            FIELD_EXPR => Expr::FieldExpr(FieldExpr { syntax }),
+            FOR_EXPR => Expr::ForExpr(ForExpr { syntax }),
+            IF_EXPR => Expr::IfExpr(IfExpr { syntax }),
+            INDEX_EXPR => Expr::IndexExpr(IndexExpr { syntax }),
+            LITERAL => Expr::Literal(Literal { syntax }),
+            LOOP_EXPR => Expr::LoopExpr(LoopExpr { syntax }),
+            MACRO_EXPR => Expr::MacroExpr(MacroExpr { syntax }),
+            MACRO_STMTS => Expr::MacroStmts(MacroStmts { syntax }),
+            MATCH_EXPR => Expr::MatchExpr(MatchExpr { syntax }),
+            METHOD_CALL_EXPR => Expr::MethodCallExpr(MethodCallExpr { syntax }),
+            PAREN_EXPR => Expr::ParenExpr(ParenExpr { syntax }),
+            PATH_EXPR => Expr::PathExpr(PathExpr { syntax }),
+            PREFIX_EXPR => Expr::PrefixExpr(PrefixExpr { syntax }),
+            RANGE_EXPR => Expr::RangeExpr(RangeExpr { syntax }),
+            RECORD_EXPR => Expr::RecordExpr(RecordExpr { syntax }),
+            REF_EXPR => Expr::RefExpr(RefExpr { syntax }),
+            RETURN_EXPR => Expr::ReturnExpr(ReturnExpr { syntax }),
+            TRY_EXPR => Expr::TryExpr(TryExpr { syntax }),
+            TUPLE_EXPR => Expr::TupleExpr(TupleExpr { syntax }),
+            WHILE_EXPR => Expr::WhileExpr(WhileExpr { syntax }),
+            YIELD_EXPR => Expr::YieldExpr(YieldExpr { syntax }),
+            LET_EXPR => Expr::LetExpr(LetExpr { syntax }),
+            UNDERSCORE_EXPR => Expr::UnderscoreExpr(UnderscoreExpr { syntax }),
+            _ => return None,
+        };
+        Some(res)
+    }
+    fn syntax(&self) -> &SyntaxNode {
+        match self {
+            Expr::ArrayExpr(it) => &it.syntax,
+            Expr::AwaitExpr(it) => &it.syntax,
+            Expr::BinExpr(it) => &it.syntax,
+            Expr::BlockExpr(it) => &it.syntax,
+            Expr::BoxExpr(it) => &it.syntax,
+            Expr::BreakExpr(it) => &it.syntax,
+            Expr::CallExpr(it) => &it.syntax,
+            Expr::CastExpr(it) => &it.syntax,
+            Expr::ClosureExpr(it) => &it.syntax,
+            Expr::ContinueExpr(it) => &it.syntax,
+            Expr::FieldExpr(it) => &it.syntax,
+            Expr::ForExpr(it) => &it.syntax,
+            Expr::IfExpr(it) => &it.syntax,
+            Expr::IndexExpr(it) => &it.syntax,
+            Expr::Literal(it) => &it.syntax,
+            Expr::LoopExpr(it) => &it.syntax,
+            Expr::MacroExpr(it) => &it.syntax,
+            Expr::MacroStmts(it) => &it.syntax,
+            Expr::MatchExpr(it) => &it.syntax,
+            Expr::MethodCallExpr(it) => &it.syntax,
+            Expr::ParenExpr(it) => &it.syntax,
+            Expr::PathExpr(it) => &it.syntax,
+            Expr::PrefixExpr(it) => &it.syntax,
+            Expr::RangeExpr(it) => &it.syntax,
+            Expr::RecordExpr(it) => &it.syntax,
+            Expr::RefExpr(it) => &it.syntax,
+            Expr::ReturnExpr(it) => &it.syntax,
+            Expr::TryExpr(it) => &it.syntax,
+            Expr::TupleExpr(it) => &it.syntax,
+            Expr::WhileExpr(it) => &it.syntax,
+            Expr::YieldExpr(it) => &it.syntax,
+            Expr::LetExpr(it) => &it.syntax,
+            Expr::UnderscoreExpr(it) => &it.syntax,
+        }
+    }
+}
+impl From<Const> for Item {
+    fn from(node: Const) -> Item { Item::Const(node) }
+}
+impl From<Enum> for Item {
+    fn from(node: Enum) -> Item { Item::Enum(node) }
+}
+impl From<ExternBlock> for Item {
+    fn from(node: ExternBlock) -> Item { Item::ExternBlock(node) }
+}
+impl From<ExternCrate> for Item {
+    fn from(node: ExternCrate) -> Item { Item::ExternCrate(node) }
+}
+impl From<Fn> for Item {
+    fn from(node: Fn) -> Item { Item::Fn(node) }
+}
+impl From<Impl> for Item {
+    fn from(node: Impl) -> Item { Item::Impl(node) }
+}
+impl From<MacroCall> for Item {
+    fn from(node: MacroCall) -> Item { Item::MacroCall(node) }
+}
+impl From<MacroRules> for Item {
+    fn from(node: MacroRules) -> Item { Item::MacroRules(node) }
+}
+impl From<MacroDef> for Item {
+    fn from(node: MacroDef) -> Item { Item::MacroDef(node) }
+}
+impl From<Module> for Item {
+    fn from(node: Module) -> Item { Item::Module(node) }
+}
+impl From<Static> for Item {
+    fn from(node: Static) -> Item { Item::Static(node) }
+}
+impl From<Struct> for Item {
+    fn from(node: Struct) -> Item { Item::Struct(node) }
+}
+impl From<Trait> for Item {
+    fn from(node: Trait) -> Item { Item::Trait(node) }
+}
+impl From<TypeAlias> for Item {
+    fn from(node: TypeAlias) -> Item { Item::TypeAlias(node) }
+}
+impl From<Union> for Item {
+    fn from(node: Union) -> Item { Item::Union(node) }
+}
+impl From<Use> for Item {
+    fn from(node: Use) -> Item { Item::Use(node) }
+}
+impl AstNode for Item {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            CONST | ENUM | EXTERN_BLOCK | EXTERN_CRATE | FN | IMPL | MACRO_CALL | MACRO_RULES
+            | MACRO_DEF | MODULE | STATIC | STRUCT | TRAIT | TYPE_ALIAS | UNION | USE => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        let res = match syntax.kind() {
+            CONST => Item::Const(Const { syntax }),
+            ENUM => Item::Enum(Enum { syntax }),
+            EXTERN_BLOCK => Item::ExternBlock(ExternBlock { syntax }),
+            EXTERN_CRATE => Item::ExternCrate(ExternCrate { syntax }),
+            FN => Item::Fn(Fn { syntax }),
+            IMPL => Item::Impl(Impl { syntax }),
+            MACRO_CALL => Item::MacroCall(MacroCall { syntax }),
+            MACRO_RULES => Item::MacroRules(MacroRules { syntax }),
+            MACRO_DEF => Item::MacroDef(MacroDef { syntax }),
+            MODULE => Item::Module(Module { syntax }),
+            STATIC => Item::Static(Static { syntax }),
+            STRUCT => Item::Struct(Struct { syntax }),
+            TRAIT => Item::Trait(Trait { syntax }),
+            TYPE_ALIAS => Item::TypeAlias(TypeAlias { syntax }),
+            UNION => Item::Union(Union { syntax }),
+            USE => Item::Use(Use { syntax }),
+            _ => return None,
+        };
+        Some(res)
+    }
+    fn syntax(&self) -> &SyntaxNode {
+        match self {
+            Item::Const(it) => &it.syntax,
+            Item::Enum(it) => &it.syntax,
+            Item::ExternBlock(it) => &it.syntax,
+            Item::ExternCrate(it) => &it.syntax,
+            Item::Fn(it) => &it.syntax,
+            Item::Impl(it) => &it.syntax,
+            Item::MacroCall(it) => &it.syntax,
+            Item::MacroRules(it) => &it.syntax,
+            Item::MacroDef(it) => &it.syntax,
+            Item::Module(it) => &it.syntax,
+            Item::Static(it) => &it.syntax,
+            Item::Struct(it) => &it.syntax,
+            Item::Trait(it) => &it.syntax,
+            Item::TypeAlias(it) => &it.syntax,
+            Item::Union(it) => &it.syntax,
+            Item::Use(it) => &it.syntax,
+        }
+    }
+}
+impl From<ExprStmt> for Stmt {
+    fn from(node: ExprStmt) -> Stmt { Stmt::ExprStmt(node) }
+}
+impl From<Item> for Stmt {
+    fn from(node: Item) -> Stmt { Stmt::Item(node) }
+}
+impl From<LetStmt> for Stmt {
+    fn from(node: LetStmt) -> Stmt { Stmt::LetStmt(node) }
+}
+impl From<IdentPat> for Pat {
+    fn from(node: IdentPat) -> Pat { Pat::IdentPat(node) }
+}
+impl From<BoxPat> for Pat {
+    fn from(node: BoxPat) -> Pat { Pat::BoxPat(node) }
+}
+impl From<RestPat> for Pat {
+    fn from(node: RestPat) -> Pat { Pat::RestPat(node) }
+}
+impl From<LiteralPat> for Pat {
+    fn from(node: LiteralPat) -> Pat { Pat::LiteralPat(node) }
+}
+impl From<MacroPat> for Pat {
+    fn from(node: MacroPat) -> Pat { Pat::MacroPat(node) }
+}
+impl From<OrPat> for Pat {
+    fn from(node: OrPat) -> Pat { Pat::OrPat(node) }
+}
+impl From<ParenPat> for Pat {
+    fn from(node: ParenPat) -> Pat { Pat::ParenPat(node) }
+}
+impl From<PathPat> for Pat {
+    fn from(node: PathPat) -> Pat { Pat::PathPat(node) }
+}
+impl From<WildcardPat> for Pat {
+    fn from(node: WildcardPat) -> Pat { Pat::WildcardPat(node) }
+}
+impl From<RangePat> for Pat {
+    fn from(node: RangePat) -> Pat { Pat::RangePat(node) }
+}
+impl From<RecordPat> for Pat {
+    fn from(node: RecordPat) -> Pat { Pat::RecordPat(node) }
+}
+impl From<RefPat> for Pat {
+    fn from(node: RefPat) -> Pat { Pat::RefPat(node) }
+}
+impl From<SlicePat> for Pat {
+    fn from(node: SlicePat) -> Pat { Pat::SlicePat(node) }
+}
+impl From<TuplePat> for Pat {
+    fn from(node: TuplePat) -> Pat { Pat::TuplePat(node) }
+}
+impl From<TupleStructPat> for Pat {
+    fn from(node: TupleStructPat) -> Pat { Pat::TupleStructPat(node) }
+}
+impl From<ConstBlockPat> for Pat {
+    fn from(node: ConstBlockPat) -> Pat { Pat::ConstBlockPat(node) }
+}
+impl AstNode for Pat {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            IDENT_PAT | BOX_PAT | REST_PAT | LITERAL_PAT | MACRO_PAT | OR_PAT | PAREN_PAT
+            | PATH_PAT | WILDCARD_PAT | RANGE_PAT | RECORD_PAT | REF_PAT | SLICE_PAT
+            | TUPLE_PAT | TUPLE_STRUCT_PAT | CONST_BLOCK_PAT => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        let res = match syntax.kind() {
+            IDENT_PAT => Pat::IdentPat(IdentPat { syntax }),
+            BOX_PAT => Pat::BoxPat(BoxPat { syntax }),
+            REST_PAT => Pat::RestPat(RestPat { syntax }),
+            LITERAL_PAT => Pat::LiteralPat(LiteralPat { syntax }),
+            MACRO_PAT => Pat::MacroPat(MacroPat { syntax }),
+            OR_PAT => Pat::OrPat(OrPat { syntax }),
+            PAREN_PAT => Pat::ParenPat(ParenPat { syntax }),
+            PATH_PAT => Pat::PathPat(PathPat { syntax }),
+            WILDCARD_PAT => Pat::WildcardPat(WildcardPat { syntax }),
+            RANGE_PAT => Pat::RangePat(RangePat { syntax }),
+            RECORD_PAT => Pat::RecordPat(RecordPat { syntax }),
+            REF_PAT => Pat::RefPat(RefPat { syntax }),
+            SLICE_PAT => Pat::SlicePat(SlicePat { syntax }),
+            TUPLE_PAT => Pat::TuplePat(TuplePat { syntax }),
+            TUPLE_STRUCT_PAT => Pat::TupleStructPat(TupleStructPat { syntax }),
+            CONST_BLOCK_PAT => Pat::ConstBlockPat(ConstBlockPat { syntax }),
+            _ => return None,
+        };
+        Some(res)
+    }
+    fn syntax(&self) -> &SyntaxNode {
+        match self {
+            Pat::IdentPat(it) => &it.syntax,
+            Pat::BoxPat(it) => &it.syntax,
+            Pat::RestPat(it) => &it.syntax,
+            Pat::LiteralPat(it) => &it.syntax,
+            Pat::MacroPat(it) => &it.syntax,
+            Pat::OrPat(it) => &it.syntax,
+            Pat::ParenPat(it) => &it.syntax,
+            Pat::PathPat(it) => &it.syntax,
+            Pat::WildcardPat(it) => &it.syntax,
+            Pat::RangePat(it) => &it.syntax,
+            Pat::RecordPat(it) => &it.syntax,
+            Pat::RefPat(it) => &it.syntax,
+            Pat::SlicePat(it) => &it.syntax,
+            Pat::TuplePat(it) => &it.syntax,
+            Pat::TupleStructPat(it) => &it.syntax,
+            Pat::ConstBlockPat(it) => &it.syntax,
+        }
+    }
+}
+impl From<RecordFieldList> for FieldList {
+    fn from(node: RecordFieldList) -> FieldList { FieldList::RecordFieldList(node) }
+}
+impl From<TupleFieldList> for FieldList {
+    fn from(node: TupleFieldList) -> FieldList { FieldList::TupleFieldList(node) }
+}
+impl AstNode for FieldList {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            RECORD_FIELD_LIST | TUPLE_FIELD_LIST => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        let res = match syntax.kind() {
+            RECORD_FIELD_LIST => FieldList::RecordFieldList(RecordFieldList { syntax }),
+            TUPLE_FIELD_LIST => FieldList::TupleFieldList(TupleFieldList { syntax }),
+            _ => return None,
+        };
+        Some(res)
+    }
+    fn syntax(&self) -> &SyntaxNode {
+        match self {
+            FieldList::RecordFieldList(it) => &it.syntax,
+            FieldList::TupleFieldList(it) => &it.syntax,
+        }
+    }
+}
+impl From<Enum> for Adt {
+    fn from(node: Enum) -> Adt { Adt::Enum(node) }
+}
+impl From<Struct> for Adt {
+    fn from(node: Struct) -> Adt { Adt::Struct(node) }
+}
+impl From<Union> for Adt {
+    fn from(node: Union) -> Adt { Adt::Union(node) }
+}
+impl AstNode for Adt {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            ENUM | STRUCT | UNION => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        let res = match syntax.kind() {
+            ENUM => Adt::Enum(Enum { syntax }),
+            STRUCT => Adt::Struct(Struct { syntax }),
+            UNION => Adt::Union(Union { syntax }),
+            _ => return None,
+        };
+        Some(res)
+    }
+    fn syntax(&self) -> &SyntaxNode {
+        match self {
+            Adt::Enum(it) => &it.syntax,
+            Adt::Struct(it) => &it.syntax,
+            Adt::Union(it) => &it.syntax,
+        }
+    }
+}
+impl From<Const> for AssocItem {
+    fn from(node: Const) -> AssocItem { AssocItem::Const(node) }
+}
+impl From<Fn> for AssocItem {
+    fn from(node: Fn) -> AssocItem { AssocItem::Fn(node) }
+}
+impl From<MacroCall> for AssocItem {
+    fn from(node: MacroCall) -> AssocItem { AssocItem::MacroCall(node) }
+}
+impl From<TypeAlias> for AssocItem {
+    fn from(node: TypeAlias) -> AssocItem { AssocItem::TypeAlias(node) }
+}
+impl AstNode for AssocItem {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            CONST | FN | MACRO_CALL | TYPE_ALIAS => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        let res = match syntax.kind() {
+            CONST => AssocItem::Const(Const { syntax }),
+            FN => AssocItem::Fn(Fn { syntax }),
+            MACRO_CALL => AssocItem::MacroCall(MacroCall { syntax }),
+            TYPE_ALIAS => AssocItem::TypeAlias(TypeAlias { syntax }),
+            _ => return None,
+        };
+        Some(res)
+    }
+    fn syntax(&self) -> &SyntaxNode {
+        match self {
+            AssocItem::Const(it) => &it.syntax,
+            AssocItem::Fn(it) => &it.syntax,
+            AssocItem::MacroCall(it) => &it.syntax,
+            AssocItem::TypeAlias(it) => &it.syntax,
+        }
+    }
+}
+impl From<Fn> for ExternItem {
+    fn from(node: Fn) -> ExternItem { ExternItem::Fn(node) }
+}
+impl From<MacroCall> for ExternItem {
+    fn from(node: MacroCall) -> ExternItem { ExternItem::MacroCall(node) }
+}
+impl From<Static> for ExternItem {
+    fn from(node: Static) -> ExternItem { ExternItem::Static(node) }
+}
+impl From<TypeAlias> for ExternItem {
+    fn from(node: TypeAlias) -> ExternItem { ExternItem::TypeAlias(node) }
+}
+impl AstNode for ExternItem {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            FN | MACRO_CALL | STATIC | TYPE_ALIAS => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        let res = match syntax.kind() {
+            FN => ExternItem::Fn(Fn { syntax }),
+            MACRO_CALL => ExternItem::MacroCall(MacroCall { syntax }),
+            STATIC => ExternItem::Static(Static { syntax }),
+            TYPE_ALIAS => ExternItem::TypeAlias(TypeAlias { syntax }),
+            _ => return None,
+        };
+        Some(res)
+    }
+    fn syntax(&self) -> &SyntaxNode {
+        match self {
+            ExternItem::Fn(it) => &it.syntax,
+            ExternItem::MacroCall(it) => &it.syntax,
+            ExternItem::Static(it) => &it.syntax,
+            ExternItem::TypeAlias(it) => &it.syntax,
+        }
+    }
+}
+impl From<ConstParam> for GenericParam {
+    fn from(node: ConstParam) -> GenericParam { GenericParam::ConstParam(node) }
+}
+impl From<LifetimeParam> for GenericParam {
+    fn from(node: LifetimeParam) -> GenericParam { GenericParam::LifetimeParam(node) }
+}
+impl From<TypeParam> for GenericParam {
+    fn from(node: TypeParam) -> GenericParam { GenericParam::TypeParam(node) }
+}
+impl AstNode for GenericParam {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            CONST_PARAM | LIFETIME_PARAM | TYPE_PARAM => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        let res = match syntax.kind() {
+            CONST_PARAM => GenericParam::ConstParam(ConstParam { syntax }),
+            LIFETIME_PARAM => GenericParam::LifetimeParam(LifetimeParam { syntax }),
+            TYPE_PARAM => GenericParam::TypeParam(TypeParam { syntax }),
+            _ => return None,
+        };
+        Some(res)
+    }
+    fn syntax(&self) -> &SyntaxNode {
+        match self {
+            GenericParam::ConstParam(it) => &it.syntax,
+            GenericParam::LifetimeParam(it) => &it.syntax,
+            GenericParam::TypeParam(it) => &it.syntax,
+        }
+    }
+}
+impl AnyHasArgList {
+    #[inline]
+    pub fn new<T: ast::HasArgList>(node: T) -> AnyHasArgList {
+        AnyHasArgList { syntax: node.syntax().clone() }
+    }
+}
+impl AstNode for AnyHasArgList {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            CALL_EXPR | METHOD_CALL_EXPR => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        Self::can_cast(syntax.kind()).then(|| AnyHasArgList { syntax })
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AnyHasAttrs {
+    #[inline]
+    pub fn new<T: ast::HasAttrs>(node: T) -> AnyHasAttrs {
+        AnyHasAttrs { syntax: node.syntax().clone() }
+    }
+}
+impl AstNode for AnyHasAttrs {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            MACRO_CALL
+            | SOURCE_FILE
+            | CONST
+            | ENUM
+            | EXTERN_BLOCK
+            | EXTERN_CRATE
+            | FN
+            | IMPL
+            | MACRO_RULES
+            | MACRO_DEF
+            | MODULE
+            | STATIC
+            | STRUCT
+            | TRAIT
+            | TYPE_ALIAS
+            | UNION
+            | USE
+            | ITEM_LIST
+            | BLOCK_EXPR
+            | SELF_PARAM
+            | PARAM
+            | RECORD_FIELD
+            | TUPLE_FIELD
+            | VARIANT
+            | ASSOC_ITEM_LIST
+            | EXTERN_ITEM_LIST
+            | CONST_PARAM
+            | LIFETIME_PARAM
+            | TYPE_PARAM
+            | LET_STMT
+            | ARRAY_EXPR
+            | AWAIT_EXPR
+            | BIN_EXPR
+            | BOX_EXPR
+            | BREAK_EXPR
+            | CALL_EXPR
+            | CAST_EXPR
+            | CLOSURE_EXPR
+            | CONTINUE_EXPR
+            | FIELD_EXPR
+            | FOR_EXPR
+            | IF_EXPR
+            | INDEX_EXPR
+            | LITERAL
+            | LOOP_EXPR
+            | MATCH_EXPR
+            | METHOD_CALL_EXPR
+            | PAREN_EXPR
+            | PATH_EXPR
+            | PREFIX_EXPR
+            | RANGE_EXPR
+            | REF_EXPR
+            | RETURN_EXPR
+            | TRY_EXPR
+            | TUPLE_EXPR
+            | WHILE_EXPR
+            | YIELD_EXPR
+            | LET_EXPR
+            | UNDERSCORE_EXPR
+            | STMT_LIST
+            | RECORD_EXPR_FIELD_LIST
+            | RECORD_EXPR_FIELD
+            | MATCH_ARM_LIST
+            | MATCH_ARM
+            | IDENT_PAT
+            | REST_PAT
+            | RECORD_PAT_FIELD => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        Self::can_cast(syntax.kind()).then(|| AnyHasAttrs { syntax })
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AnyHasDocComments {
+    #[inline]
+    pub fn new<T: ast::HasDocComments>(node: T) -> AnyHasDocComments {
+        AnyHasDocComments { syntax: node.syntax().clone() }
+    }
+}
+impl AstNode for AnyHasDocComments {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            MACRO_CALL | SOURCE_FILE | CONST | ENUM | EXTERN_BLOCK | EXTERN_CRATE | FN | IMPL
+            | MACRO_RULES | MACRO_DEF | MODULE | STATIC | STRUCT | TRAIT | TYPE_ALIAS | UNION
+            | USE | RECORD_FIELD | TUPLE_FIELD | VARIANT => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        Self::can_cast(syntax.kind()).then(|| AnyHasDocComments { syntax })
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AnyHasGenericParams {
+    #[inline]
+    pub fn new<T: ast::HasGenericParams>(node: T) -> AnyHasGenericParams {
+        AnyHasGenericParams { syntax: node.syntax().clone() }
+    }
+}
+impl AstNode for AnyHasGenericParams {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            ENUM | FN | IMPL | STRUCT | TRAIT | TYPE_ALIAS | UNION => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        Self::can_cast(syntax.kind()).then(|| AnyHasGenericParams { syntax })
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AnyHasLoopBody {
+    #[inline]
+    pub fn new<T: ast::HasLoopBody>(node: T) -> AnyHasLoopBody {
+        AnyHasLoopBody { syntax: node.syntax().clone() }
+    }
+}
+impl AstNode for AnyHasLoopBody {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            FOR_EXPR | LOOP_EXPR | WHILE_EXPR => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        Self::can_cast(syntax.kind()).then(|| AnyHasLoopBody { syntax })
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AnyHasModuleItem {
+    #[inline]
+    pub fn new<T: ast::HasModuleItem>(node: T) -> AnyHasModuleItem {
+        AnyHasModuleItem { syntax: node.syntax().clone() }
+    }
+}
+impl AstNode for AnyHasModuleItem {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            MACRO_ITEMS | SOURCE_FILE | ITEM_LIST => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        Self::can_cast(syntax.kind()).then(|| AnyHasModuleItem { syntax })
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AnyHasName {
+    #[inline]
+    pub fn new<T: ast::HasName>(node: T) -> AnyHasName {
+        AnyHasName { syntax: node.syntax().clone() }
+    }
+}
+impl AstNode for AnyHasName {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            CONST | ENUM | FN | MACRO_RULES | MACRO_DEF | MODULE | STATIC | STRUCT | TRAIT
+            | TYPE_ALIAS | UNION | RENAME | SELF_PARAM | RECORD_FIELD | VARIANT | CONST_PARAM
+            | TYPE_PARAM | IDENT_PAT => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        Self::can_cast(syntax.kind()).then(|| AnyHasName { syntax })
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AnyHasTypeBounds {
+    #[inline]
+    pub fn new<T: ast::HasTypeBounds>(node: T) -> AnyHasTypeBounds {
+        AnyHasTypeBounds { syntax: node.syntax().clone() }
+    }
+}
+impl AstNode for AnyHasTypeBounds {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            ASSOC_TYPE_ARG | TRAIT | TYPE_ALIAS | LIFETIME_PARAM | TYPE_PARAM | WHERE_PRED => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        Self::can_cast(syntax.kind()).then(|| AnyHasTypeBounds { syntax })
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl AnyHasVisibility {
+    #[inline]
+    pub fn new<T: ast::HasVisibility>(node: T) -> AnyHasVisibility {
+        AnyHasVisibility { syntax: node.syntax().clone() }
+    }
+}
+impl AstNode for AnyHasVisibility {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            CONST | ENUM | EXTERN_CRATE | FN | IMPL | MACRO_RULES | MACRO_DEF | MODULE | STATIC
+            | STRUCT | TRAIT | TYPE_ALIAS | UNION | USE | RECORD_FIELD | TUPLE_FIELD | VARIANT => {
+                true
+            }
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        Self::can_cast(syntax.kind()).then(|| AnyHasVisibility { syntax })
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
+impl std::fmt::Display for GenericArg {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Type {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Expr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Item {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Stmt {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Pat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for FieldList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Adt {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for AssocItem {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ExternItem {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for GenericParam {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Name {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for NameRef {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Lifetime {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Path {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for PathSegment {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for GenericArgList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ParamList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for RetType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for PathType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for TypeArg {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for AssocTypeArg {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for LifetimeArg {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ConstArg {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for GenericParamList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for TypeBoundList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for MacroCall {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Attr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for TokenTree {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for MacroItems {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for MacroStmts {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for SourceFile {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Const {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Enum {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ExternBlock {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ExternCrate {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Fn {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Impl {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for MacroRules {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for MacroDef {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Module {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Static {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Struct {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Trait {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for TypeAlias {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Union {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Use {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Visibility {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ItemList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Rename {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for UseTree {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for UseTreeList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Abi {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for WhereClause {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for BlockExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for SelfParam {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Param {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for RecordFieldList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for TupleFieldList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for RecordField {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for TupleField {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for VariantList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Variant {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for AssocItemList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ExternItemList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ConstParam {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for LifetimeParam {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for TypeParam {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for WherePred {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Meta {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ExprStmt {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for LetStmt {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for LetElse {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ArrayExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for AwaitExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for BinExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for BoxExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for BreakExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for CallExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for CastExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ClosureExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ContinueExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for FieldExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ForExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for IfExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for IndexExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Literal {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for LoopExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for MacroExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for MatchExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for MethodCallExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ParenExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for PathExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for PrefixExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for RangeExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for RecordExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for RefExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ReturnExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for TryExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for TupleExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for WhileExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for YieldExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for LetExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for UnderscoreExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for StmtList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for Label {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for RecordExprFieldList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for RecordExprField {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ArgList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for MatchArmList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for MatchArm {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for MatchGuard {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ArrayType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for DynTraitType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for FnPtrType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ForType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ImplTraitType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for InferType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for MacroType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for NeverType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ParenType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for PtrType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for RefType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for SliceType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for TupleType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for TypeBound {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for IdentPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for BoxPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for RestPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for LiteralPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for MacroPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for OrPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ParenPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for PathPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for WildcardPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for RangePat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for RecordPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for RefPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for SlicePat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for TuplePat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for TupleStructPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for ConstBlockPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for RecordPatFieldList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl std::fmt::Display for RecordPatField {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ast/generated/tokens.rs b/src/tools/rust-analyzer/crates/syntax/src/ast/generated/tokens.rs
new file mode 100644
index 000000000..a3209c5ab
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/ast/generated/tokens.rs
@@ -0,0 +1,196 @@
+//! Generated by `sourcegen_ast`, do not edit by hand.
+
+use crate::{
+    ast::AstToken,
+    SyntaxKind::{self, *},
+    SyntaxToken,
+};
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Whitespace {
+    pub(crate) syntax: SyntaxToken,
+}
+impl std::fmt::Display for Whitespace {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(&self.syntax, f)
+    }
+}
+impl AstToken for Whitespace {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == WHITESPACE }
+    fn cast(syntax: SyntaxToken) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxToken { &self.syntax }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Comment {
+    pub(crate) syntax: SyntaxToken,
+}
+impl std::fmt::Display for Comment {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(&self.syntax, f)
+    }
+}
+impl AstToken for Comment {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == COMMENT }
+    fn cast(syntax: SyntaxToken) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxToken { &self.syntax }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct String {
+    pub(crate) syntax: SyntaxToken,
+}
+impl std::fmt::Display for String {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(&self.syntax, f)
+    }
+}
+impl AstToken for String {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == STRING }
+    fn cast(syntax: SyntaxToken) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxToken { &self.syntax }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ByteString {
+    pub(crate) syntax: SyntaxToken,
+}
+impl std::fmt::Display for ByteString {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(&self.syntax, f)
+    }
+}
+impl AstToken for ByteString {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == BYTE_STRING }
+    fn cast(syntax: SyntaxToken) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxToken { &self.syntax }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct IntNumber {
+    pub(crate) syntax: SyntaxToken,
+}
+impl std::fmt::Display for IntNumber {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(&self.syntax, f)
+    }
+}
+impl AstToken for IntNumber {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == INT_NUMBER }
+    fn cast(syntax: SyntaxToken) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxToken { &self.syntax }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct FloatNumber {
+    pub(crate) syntax: SyntaxToken,
+}
+impl std::fmt::Display for FloatNumber {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(&self.syntax, f)
+    }
+}
+impl AstToken for FloatNumber {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == FLOAT_NUMBER }
+    fn cast(syntax: SyntaxToken) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxToken { &self.syntax }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Char {
+    pub(crate) syntax: SyntaxToken,
+}
+impl std::fmt::Display for Char {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(&self.syntax, f)
+    }
+}
+impl AstToken for Char {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == CHAR }
+    fn cast(syntax: SyntaxToken) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxToken { &self.syntax }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Byte {
+    pub(crate) syntax: SyntaxToken,
+}
+impl std::fmt::Display for Byte {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(&self.syntax, f)
+    }
+}
+impl AstToken for Byte {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == BYTE }
+    fn cast(syntax: SyntaxToken) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxToken { &self.syntax }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Ident {
+    pub(crate) syntax: SyntaxToken,
+}
+impl std::fmt::Display for Ident {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(&self.syntax, f)
+    }
+}
+impl AstToken for Ident {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == IDENT }
+    fn cast(syntax: SyntaxToken) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxToken { &self.syntax }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ast/make.rs b/src/tools/rust-analyzer/crates/syntax/src/ast/make.rs
new file mode 100644
index 000000000..5908dda8e
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/ast/make.rs
@@ -0,0 +1,901 @@
+//! This module contains free-standing functions for creating AST fragments out
+//! of smaller pieces.
+//!
+//! Note that all functions here intended to be stupid constructors, which just
+//! assemble a finish node from immediate children. If you want to do something
+//! smarter than that, it belongs to the `ext` submodule.
+//!
+//! Keep in mind that `from_text` functions should be kept private. The public
+//! API should require to assemble every node piecewise. The trick of
+//! `parse(format!())` we use internally is an implementation detail -- long
+//! term, it will be replaced with direct tree manipulation.
+use itertools::Itertools;
+use stdx::{format_to, never};
+
+use crate::{ast, AstNode, SourceFile, SyntaxKind, SyntaxToken};
+
+/// While the parent module defines basic atomic "constructors", the `ext`
+/// module defines shortcuts for common things.
+///
+/// It's named `ext` rather than `shortcuts` just to keep it short.
+pub mod ext {
+    use super::*;
+
+    pub fn simple_ident_pat(name: ast::Name) -> ast::IdentPat {
+        return from_text(&name.text());
+
+        fn from_text(text: &str) -> ast::IdentPat {
+            ast_from_text(&format!("fn f({}: ())", text))
+        }
+    }
+    pub fn ident_path(ident: &str) -> ast::Path {
+        path_unqualified(path_segment(name_ref(ident)))
+    }
+
+    pub fn path_from_idents<'a>(
+        parts: impl std::iter::IntoIterator<Item = &'a str>,
+    ) -> Option<ast::Path> {
+        let mut iter = parts.into_iter();
+        let base = ext::ident_path(iter.next()?);
+        let path = iter.fold(base, |base, s| {
+            let path = ext::ident_path(s);
+            path_concat(base, path)
+        });
+        Some(path)
+    }
+
+    pub fn field_from_idents<'a>(
+        parts: impl std::iter::IntoIterator<Item = &'a str>,
+    ) -> Option<ast::Expr> {
+        let mut iter = parts.into_iter();
+        let base = expr_path(ext::ident_path(iter.next()?));
+        let expr = iter.fold(base, expr_field);
+        Some(expr)
+    }
+
+    pub fn expr_unreachable() -> ast::Expr {
+        expr_from_text("unreachable!()")
+    }
+    pub fn expr_todo() -> ast::Expr {
+        expr_from_text("todo!()")
+    }
+    pub fn expr_ty_default(ty: &ast::Type) -> ast::Expr {
+        expr_from_text(&format!("{}::default()", ty))
+    }
+    pub fn expr_ty_new(ty: &ast::Type) -> ast::Expr {
+        expr_from_text(&format!("{}::new()", ty))
+    }
+
+    pub fn zero_number() -> ast::Expr {
+        expr_from_text("0")
+    }
+    pub fn zero_float() -> ast::Expr {
+        expr_from_text("0.0")
+    }
+    pub fn empty_str() -> ast::Expr {
+        expr_from_text(r#""""#)
+    }
+    pub fn empty_char() -> ast::Expr {
+        expr_from_text("'\x00'")
+    }
+    pub fn default_bool() -> ast::Expr {
+        expr_from_text("false")
+    }
+    pub fn option_none() -> ast::Expr {
+        expr_from_text("None")
+    }
+    pub fn empty_block_expr() -> ast::BlockExpr {
+        block_expr(None, None)
+    }
+
+    pub fn ty_bool() -> ast::Type {
+        ty_path(ident_path("bool"))
+    }
+    pub fn ty_option(t: ast::Type) -> ast::Type {
+        ty_from_text(&format!("Option<{}>", t))
+    }
+    pub fn ty_result(t: ast::Type, e: ast::Type) -> ast::Type {
+        ty_from_text(&format!("Result<{}, {}>", t, e))
+    }
+}
+
+pub fn name(text: &str) -> ast::Name {
+    ast_from_text(&format!("mod {}{};", raw_ident_esc(text), text))
+}
+pub fn name_ref(text: &str) -> ast::NameRef {
+    ast_from_text(&format!("fn f() {{ {}{}; }}", raw_ident_esc(text), text))
+}
+fn raw_ident_esc(ident: &str) -> &'static str {
+    let is_keyword = parser::SyntaxKind::from_keyword(ident).is_some();
+    if is_keyword && !matches!(ident, "self" | "crate" | "super" | "Self") {
+        "r#"
+    } else {
+        ""
+    }
+}
+
+pub fn lifetime(text: &str) -> ast::Lifetime {
+    let mut text = text;
+    let tmp;
+    if never!(!text.starts_with('\'')) {
+        tmp = format!("'{}", text);
+        text = &tmp;
+    }
+    ast_from_text(&format!("fn f<{}>() {{ }}", text))
+}
+
+// FIXME: replace stringly-typed constructor with a family of typed ctors, a-la
+// `expr_xxx`.
+pub fn ty(text: &str) -> ast::Type {
+    ty_from_text(text)
+}
+pub fn ty_placeholder() -> ast::Type {
+    ty_from_text("_")
+}
+pub fn ty_unit() -> ast::Type {
+    ty_from_text("()")
+}
+pub fn ty_tuple(types: impl IntoIterator<Item = ast::Type>) -> ast::Type {
+    let mut count: usize = 0;
+    let mut contents = types.into_iter().inspect(|_| count += 1).join(", ");
+    if count == 1 {
+        contents.push(',');
+    }
+
+    ty_from_text(&format!("({})", contents))
+}
+pub fn ty_ref(target: ast::Type, exclusive: bool) -> ast::Type {
+    ty_from_text(&if exclusive { format!("&mut {}", target) } else { format!("&{}", target) })
+}
+pub fn ty_path(path: ast::Path) -> ast::Type {
+    ty_from_text(&path.to_string())
+}
+fn ty_from_text(text: &str) -> ast::Type {
+    ast_from_text(&format!("type _T = {};", text))
+}
+
+pub fn assoc_item_list() -> ast::AssocItemList {
+    ast_from_text("impl C for D {}")
+}
+
+pub fn impl_(
+    ty: ast::Path,
+    params: Option<ast::GenericParamList>,
+    ty_params: Option<ast::GenericParamList>,
+) -> ast::Impl {
+    let params = match params {
+        Some(params) => params.to_string(),
+        None => String::new(),
+    };
+    let ty_params = match ty_params {
+        Some(params) => params.to_string(),
+        None => String::new(),
+    };
+    ast_from_text(&format!("impl{} {}{} {{}}", params, ty, ty_params))
+}
+
+pub fn impl_trait(
+    trait_: ast::Path,
+    ty: ast::Path,
+    ty_params: Option<ast::GenericParamList>,
+) -> ast::Impl {
+    let ty_params = ty_params.map_or_else(String::new, |params| params.to_string());
+    ast_from_text(&format!("impl{2} {} for {}{2} {{}}", trait_, ty, ty_params))
+}
+
+pub(crate) fn generic_arg_list() -> ast::GenericArgList {
+    ast_from_text("const S: T<> = ();")
+}
+
+pub fn path_segment(name_ref: ast::NameRef) -> ast::PathSegment {
+    ast_from_text(&format!("type __ = {};", name_ref))
+}
+
+pub fn path_segment_ty(type_ref: ast::Type, trait_ref: Option<ast::PathType>) -> ast::PathSegment {
+    let text = match trait_ref {
+        Some(trait_ref) => format!("fn f(x: <{} as {}>) {{}}", type_ref, trait_ref),
+        None => format!("fn f(x: <{}>) {{}}", type_ref),
+    };
+    ast_from_text(&text)
+}
+
+pub fn path_segment_self() -> ast::PathSegment {
+    ast_from_text("use self;")
+}
+
+pub fn path_segment_super() -> ast::PathSegment {
+    ast_from_text("use super;")
+}
+
+pub fn path_segment_crate() -> ast::PathSegment {
+    ast_from_text("use crate;")
+}
+
+pub fn path_unqualified(segment: ast::PathSegment) -> ast::Path {
+    ast_from_text(&format!("type __ = {};", segment))
+}
+
+pub fn path_qualified(qual: ast::Path, segment: ast::PathSegment) -> ast::Path {
+    ast_from_text(&format!("{}::{}", qual, segment))
+}
+// FIXME: path concatenation operation doesn't make sense as AST op.
+pub fn path_concat(first: ast::Path, second: ast::Path) -> ast::Path {
+    ast_from_text(&format!("type __ = {}::{};", first, second))
+}
+
+pub fn path_from_segments(
+    segments: impl IntoIterator<Item = ast::PathSegment>,
+    is_abs: bool,
+) -> ast::Path {
+    let segments = segments.into_iter().map(|it| it.syntax().clone()).join("::");
+    ast_from_text(&if is_abs {
+        format!("fn f(x: ::{}) {{}}", segments)
+    } else {
+        format!("fn f(x: {}) {{}}", segments)
+    })
+}
+
+pub fn join_paths(paths: impl IntoIterator<Item = ast::Path>) -> ast::Path {
+    let paths = paths.into_iter().map(|it| it.syntax().clone()).join("::");
+    ast_from_text(&format!("type __ = {};", paths))
+}
+
+// FIXME: should not be pub
+pub fn path_from_text(text: &str) -> ast::Path {
+    ast_from_text(&format!("fn main() {{ let test = {}; }}", text))
+}
+
+pub fn use_tree_glob() -> ast::UseTree {
+    ast_from_text("use *;")
+}
+pub fn use_tree(
+    path: ast::Path,
+    use_tree_list: Option<ast::UseTreeList>,
+    alias: Option<ast::Rename>,
+    add_star: bool,
+) -> ast::UseTree {
+    let mut buf = "use ".to_string();
+    buf += &path.syntax().to_string();
+    if let Some(use_tree_list) = use_tree_list {
+        format_to!(buf, "::{}", use_tree_list);
+    }
+    if add_star {
+        buf += "::*";
+    }
+
+    if let Some(alias) = alias {
+        format_to!(buf, " {}", alias);
+    }
+    ast_from_text(&buf)
+}
+
+pub fn use_tree_list(use_trees: impl IntoIterator<Item = ast::UseTree>) -> ast::UseTreeList {
+    let use_trees = use_trees.into_iter().map(|it| it.syntax().clone()).join(", ");
+    ast_from_text(&format!("use {{{}}};", use_trees))
+}
+
+pub fn use_(visibility: Option<ast::Visibility>, use_tree: ast::UseTree) -> ast::Use {
+    let visibility = match visibility {
+        None => String::new(),
+        Some(it) => format!("{} ", it),
+    };
+    ast_from_text(&format!("{}use {};", visibility, use_tree))
+}
+
+pub fn record_expr(path: ast::Path, fields: ast::RecordExprFieldList) -> ast::RecordExpr {
+    ast_from_text(&format!("fn f() {{ {} {} }}", path, fields))
+}
+
+pub fn record_expr_field_list(
+    fields: impl IntoIterator<Item = ast::RecordExprField>,
+) -> ast::RecordExprFieldList {
+    let fields = fields.into_iter().join(", ");
+    ast_from_text(&format!("fn f() {{ S {{ {} }} }}", fields))
+}
+
+pub fn record_expr_field(name: ast::NameRef, expr: Option<ast::Expr>) -> ast::RecordExprField {
+    return match expr {
+        Some(expr) => from_text(&format!("{}: {}", name, expr)),
+        None => from_text(&name.to_string()),
+    };
+
+    fn from_text(text: &str) -> ast::RecordExprField {
+        ast_from_text(&format!("fn f() {{ S {{ {}, }} }}", text))
+    }
+}
+
+pub fn record_field(
+    visibility: Option<ast::Visibility>,
+    name: ast::Name,
+    ty: ast::Type,
+) -> ast::RecordField {
+    let visibility = match visibility {
+        None => String::new(),
+        Some(it) => format!("{} ", it),
+    };
+    ast_from_text(&format!("struct S {{ {}{}: {}, }}", visibility, name, ty))
+}
+
+// TODO
+pub fn block_expr(
+    stmts: impl IntoIterator<Item = ast::Stmt>,
+    tail_expr: Option<ast::Expr>,
+) -> ast::BlockExpr {
+    let mut buf = "{\n".to_string();
+    for stmt in stmts.into_iter() {
+        format_to!(buf, "    {}\n", stmt);
+    }
+    if let Some(tail_expr) = tail_expr {
+        format_to!(buf, "    {}\n", tail_expr);
+    }
+    buf += "}";
+    ast_from_text(&format!("fn f() {}", buf))
+}
+
+/// Ideally this function wouldn't exist since it involves manual indenting.
+/// It differs from `make::block_expr` by also supporting comments.
+///
+/// FIXME: replace usages of this with the mutable syntax tree API
+pub fn hacky_block_expr_with_comments(
+    elements: impl IntoIterator<Item = crate::SyntaxElement>,
+    tail_expr: Option<ast::Expr>,
+) -> ast::BlockExpr {
+    let mut buf = "{\n".to_string();
+    for node_or_token in elements.into_iter() {
+        match node_or_token {
+            rowan::NodeOrToken::Node(n) => format_to!(buf, "    {}\n", n),
+            rowan::NodeOrToken::Token(t) if t.kind() == SyntaxKind::COMMENT => {
+                format_to!(buf, "    {}\n", t)
+            }
+            _ => (),
+        }
+    }
+    if let Some(tail_expr) = tail_expr {
+        format_to!(buf, "    {}\n", tail_expr);
+    }
+    buf += "}";
+    ast_from_text(&format!("fn f() {}", buf))
+}
+
+pub fn expr_unit() -> ast::Expr {
+    expr_from_text("()")
+}
+pub fn expr_literal(text: &str) -> ast::Literal {
+    assert_eq!(text.trim(), text);
+    ast_from_text(&format!("fn f() {{ let _ = {}; }}", text))
+}
+
+pub fn expr_empty_block() -> ast::Expr {
+    expr_from_text("{}")
+}
+pub fn expr_path(path: ast::Path) -> ast::Expr {
+    expr_from_text(&path.to_string())
+}
+pub fn expr_continue(label: Option<ast::Lifetime>) -> ast::Expr {
+    match label {
+        Some(label) => expr_from_text(&format!("continue {}", label)),
+        None => expr_from_text("continue"),
+    }
+}
+// Consider `op: SyntaxKind` instead for nicer syntax at the call-site?
+pub fn expr_bin_op(lhs: ast::Expr, op: ast::BinaryOp, rhs: ast::Expr) -> ast::Expr {
+    expr_from_text(&format!("{} {} {}", lhs, op, rhs))
+}
+pub fn expr_break(label: Option<ast::Lifetime>, expr: Option<ast::Expr>) -> ast::Expr {
+    let mut s = String::from("break");
+
+    if let Some(label) = label {
+        format_to!(s, " {}", label);
+    }
+
+    if let Some(expr) = expr {
+        format_to!(s, " {}", expr);
+    }
+
+    expr_from_text(&s)
+}
+pub fn expr_return(expr: Option<ast::Expr>) -> ast::Expr {
+    match expr {
+        Some(expr) => expr_from_text(&format!("return {}", expr)),
+        None => expr_from_text("return"),
+    }
+}
+pub fn expr_try(expr: ast::Expr) -> ast::Expr {
+    expr_from_text(&format!("{}?", expr))
+}
+pub fn expr_await(expr: ast::Expr) -> ast::Expr {
+    expr_from_text(&format!("{}.await", expr))
+}
+pub fn expr_match(expr: ast::Expr, match_arm_list: ast::MatchArmList) -> ast::Expr {
+    expr_from_text(&format!("match {} {}", expr, match_arm_list))
+}
+pub fn expr_if(
+    condition: ast::Expr,
+    then_branch: ast::BlockExpr,
+    else_branch: Option<ast::ElseBranch>,
+) -> ast::Expr {
+    let else_branch = match else_branch {
+        Some(ast::ElseBranch::Block(block)) => format!("else {}", block),
+        Some(ast::ElseBranch::IfExpr(if_expr)) => format!("else {}", if_expr),
+        None => String::new(),
+    };
+    expr_from_text(&format!("if {} {} {}", condition, then_branch, else_branch))
+}
+pub fn expr_for_loop(pat: ast::Pat, expr: ast::Expr, block: ast::BlockExpr) -> ast::Expr {
+    expr_from_text(&format!("for {} in {} {}", pat, expr, block))
+}
+
+pub fn expr_loop(block: ast::BlockExpr) -> ast::Expr {
+    expr_from_text(&format!("loop {}", block))
+}
+
+pub fn expr_prefix(op: SyntaxKind, expr: ast::Expr) -> ast::Expr {
+    let token = token(op);
+    expr_from_text(&format!("{}{}", token, expr))
+}
+pub fn expr_call(f: ast::Expr, arg_list: ast::ArgList) -> ast::Expr {
+    expr_from_text(&format!("{}{}", f, arg_list))
+}
+pub fn expr_method_call(
+    receiver: ast::Expr,
+    method: ast::NameRef,
+    arg_list: ast::ArgList,
+) -> ast::Expr {
+    expr_from_text(&format!("{}.{}{}", receiver, method, arg_list))
+}
+pub fn expr_macro_call(f: ast::Expr, arg_list: ast::ArgList) -> ast::Expr {
+    expr_from_text(&format!("{}!{}", f, arg_list))
+}
+pub fn expr_ref(expr: ast::Expr, exclusive: bool) -> ast::Expr {
+    expr_from_text(&if exclusive { format!("&mut {}", expr) } else { format!("&{}", expr) })
+}
+pub fn expr_closure(pats: impl IntoIterator<Item = ast::Param>, expr: ast::Expr) -> ast::Expr {
+    let params = pats.into_iter().join(", ");
+    expr_from_text(&format!("|{}| {}", params, expr))
+}
+pub fn expr_field(receiver: ast::Expr, field: &str) -> ast::Expr {
+    expr_from_text(&format!("{}.{}", receiver, field))
+}
+pub fn expr_paren(expr: ast::Expr) -> ast::Expr {
+    expr_from_text(&format!("({})", expr))
+}
+pub fn expr_tuple(elements: impl IntoIterator<Item = ast::Expr>) -> ast::Expr {
+    let expr = elements.into_iter().format(", ");
+    expr_from_text(&format!("({})", expr))
+}
+pub fn expr_assignment(lhs: ast::Expr, rhs: ast::Expr) -> ast::Expr {
+    expr_from_text(&format!("{} = {}", lhs, rhs))
+}
+fn expr_from_text(text: &str) -> ast::Expr {
+    ast_from_text(&format!("const C: () = {};", text))
+}
+pub fn expr_let(pattern: ast::Pat, expr: ast::Expr) -> ast::LetExpr {
+    ast_from_text(&format!("const _: () = while let {} = {} {{}};", pattern, expr))
+}
+
+pub fn arg_list(args: impl IntoIterator<Item = ast::Expr>) -> ast::ArgList {
+    ast_from_text(&format!("fn main() {{ ()({}) }}", args.into_iter().format(", ")))
+}
+
+pub fn ident_pat(ref_: bool, mut_: bool, name: ast::Name) -> ast::IdentPat {
+    let mut s = String::from("fn f(");
+    if ref_ {
+        s.push_str("ref ");
+    }
+    if mut_ {
+        s.push_str("mut ");
+    }
+    format_to!(s, "{}", name);
+    s.push_str(": ())");
+    ast_from_text(&s)
+}
+
+pub fn wildcard_pat() -> ast::WildcardPat {
+    return from_text("_");
+
+    fn from_text(text: &str) -> ast::WildcardPat {
+        ast_from_text(&format!("fn f({}: ())", text))
+    }
+}
+
+pub fn literal_pat(lit: &str) -> ast::LiteralPat {
+    return from_text(lit);
+
+    fn from_text(text: &str) -> ast::LiteralPat {
+        ast_from_text(&format!("fn f() {{ match x {{ {} => {{}} }} }}", text))
+    }
+}
+
+/// Creates a tuple of patterns from an iterator of patterns.
+///
+/// Invariant: `pats` must be length > 0
+pub fn tuple_pat(pats: impl IntoIterator<Item = ast::Pat>) -> ast::TuplePat {
+    let mut count: usize = 0;
+    let mut pats_str = pats.into_iter().inspect(|_| count += 1).join(", ");
+    if count == 1 {
+        pats_str.push(',');
+    }
+    return from_text(&format!("({})", pats_str));
+
+    fn from_text(text: &str) -> ast::TuplePat {
+        ast_from_text(&format!("fn f({}: ())", text))
+    }
+}
+
+pub fn tuple_struct_pat(
+    path: ast::Path,
+    pats: impl IntoIterator<Item = ast::Pat>,
+) -> ast::TupleStructPat {
+    let pats_str = pats.into_iter().join(", ");
+    return from_text(&format!("{}({})", path, pats_str));
+
+    fn from_text(text: &str) -> ast::TupleStructPat {
+        ast_from_text(&format!("fn f({}: ())", text))
+    }
+}
+
+pub fn record_pat(path: ast::Path, pats: impl IntoIterator<Item = ast::Pat>) -> ast::RecordPat {
+    let pats_str = pats.into_iter().join(", ");
+    return from_text(&format!("{} {{ {} }}", path, pats_str));
+
+    fn from_text(text: &str) -> ast::RecordPat {
+        ast_from_text(&format!("fn f({}: ())", text))
+    }
+}
+
+pub fn record_pat_with_fields(path: ast::Path, fields: ast::RecordPatFieldList) -> ast::RecordPat {
+    ast_from_text(&format!("fn f({} {}: ()))", path, fields))
+}
+
+pub fn record_pat_field_list(
+    fields: impl IntoIterator<Item = ast::RecordPatField>,
+) -> ast::RecordPatFieldList {
+    let fields = fields.into_iter().join(", ");
+    ast_from_text(&format!("fn f(S {{ {} }}: ()))", fields))
+}
+
+pub fn record_pat_field(name_ref: ast::NameRef, pat: ast::Pat) -> ast::RecordPatField {
+    ast_from_text(&format!("fn f(S {{ {}: {} }}: ()))", name_ref, pat))
+}
+
+pub fn record_pat_field_shorthand(name_ref: ast::NameRef) -> ast::RecordPatField {
+    ast_from_text(&format!("fn f(S {{ {} }}: ()))", name_ref))
+}
+
+/// Returns a `BindPat` if the path has just one segment, a `PathPat` otherwise.
+pub fn path_pat(path: ast::Path) -> ast::Pat {
+    return from_text(&path.to_string());
+    fn from_text(text: &str) -> ast::Pat {
+        ast_from_text(&format!("fn f({}: ())", text))
+    }
+}
+
+pub fn match_arm(
+    pats: impl IntoIterator<Item = ast::Pat>,
+    guard: Option<ast::Expr>,
+    expr: ast::Expr,
+) -> ast::MatchArm {
+    let pats_str = pats.into_iter().join(" | ");
+    return match guard {
+        Some(guard) => from_text(&format!("{} if {} => {}", pats_str, guard, expr)),
+        None => from_text(&format!("{} => {}", pats_str, expr)),
+    };
+
+    fn from_text(text: &str) -> ast::MatchArm {
+        ast_from_text(&format!("fn f() {{ match () {{{}}} }}", text))
+    }
+}
+
+pub fn match_arm_with_guard(
+    pats: impl IntoIterator<Item = ast::Pat>,
+    guard: ast::Expr,
+    expr: ast::Expr,
+) -> ast::MatchArm {
+    let pats_str = pats.into_iter().join(" | ");
+    return from_text(&format!("{} if {} => {}", pats_str, guard, expr));
+
+    fn from_text(text: &str) -> ast::MatchArm {
+        ast_from_text(&format!("fn f() {{ match () {{{}}} }}", text))
+    }
+}
+
+pub fn match_arm_list(arms: impl IntoIterator<Item = ast::MatchArm>) -> ast::MatchArmList {
+    let arms_str = arms
+        .into_iter()
+        .map(|arm| {
+            let needs_comma = arm.expr().map_or(true, |it| !it.is_block_like());
+            let comma = if needs_comma { "," } else { "" };
+            format!("    {}{}\n", arm.syntax(), comma)
+        })
+        .collect::<String>();
+    return from_text(&arms_str);
+
+    fn from_text(text: &str) -> ast::MatchArmList {
+        ast_from_text(&format!("fn f() {{ match () {{\n{}}} }}", text))
+    }
+}
+
+pub fn where_pred(
+    path: ast::Path,
+    bounds: impl IntoIterator<Item = ast::TypeBound>,
+) -> ast::WherePred {
+    let bounds = bounds.into_iter().join(" + ");
+    return from_text(&format!("{}: {}", path, bounds));
+
+    fn from_text(text: &str) -> ast::WherePred {
+        ast_from_text(&format!("fn f() where {} {{ }}", text))
+    }
+}
+
+pub fn where_clause(preds: impl IntoIterator<Item = ast::WherePred>) -> ast::WhereClause {
+    let preds = preds.into_iter().join(", ");
+    return from_text(preds.as_str());
+
+    fn from_text(text: &str) -> ast::WhereClause {
+        ast_from_text(&format!("fn f() where {} {{ }}", text))
+    }
+}
+
+pub fn let_stmt(
+    pattern: ast::Pat,
+    ty: Option<ast::Type>,
+    initializer: Option<ast::Expr>,
+) -> ast::LetStmt {
+    let mut text = String::new();
+    format_to!(text, "let {}", pattern);
+    if let Some(ty) = ty {
+        format_to!(text, ": {}", ty);
+    }
+    match initializer {
+        Some(it) => format_to!(text, " = {};", it),
+        None => format_to!(text, ";"),
+    };
+    ast_from_text(&format!("fn f() {{ {} }}", text))
+}
+pub fn expr_stmt(expr: ast::Expr) -> ast::ExprStmt {
+    let semi = if expr.is_block_like() { "" } else { ";" };
+    ast_from_text(&format!("fn f() {{ {}{} (); }}", expr, semi))
+}
+
+pub fn item_const(
+    visibility: Option<ast::Visibility>,
+    name: ast::Name,
+    ty: ast::Type,
+    expr: ast::Expr,
+) -> ast::Const {
+    let visibility = match visibility {
+        None => String::new(),
+        Some(it) => format!("{} ", it),
+    };
+    ast_from_text(&format!("{} const {}: {} = {};", visibility, name, ty, expr))
+}
+
+pub fn param(pat: ast::Pat, ty: ast::Type) -> ast::Param {
+    ast_from_text(&format!("fn f({}: {}) {{ }}", pat, ty))
+}
+
+pub fn self_param() -> ast::SelfParam {
+    ast_from_text("fn f(&self) { }")
+}
+
+pub fn ret_type(ty: ast::Type) -> ast::RetType {
+    ast_from_text(&format!("fn f() -> {} {{ }}", ty))
+}
+
+pub fn param_list(
+    self_param: Option<ast::SelfParam>,
+    pats: impl IntoIterator<Item = ast::Param>,
+) -> ast::ParamList {
+    let args = pats.into_iter().join(", ");
+    let list = match self_param {
+        Some(self_param) if args.is_empty() => format!("fn f({}) {{ }}", self_param),
+        Some(self_param) => format!("fn f({}, {}) {{ }}", self_param, args),
+        None => format!("fn f({}) {{ }}", args),
+    };
+    ast_from_text(&list)
+}
+
+pub fn type_param(name: ast::Name, ty: Option<ast::TypeBoundList>) -> ast::TypeParam {
+    let bound = match ty {
+        Some(it) => format!(": {}", it),
+        None => String::new(),
+    };
+    ast_from_text(&format!("fn f<{}{}>() {{ }}", name, bound))
+}
+
+pub fn lifetime_param(lifetime: ast::Lifetime) -> ast::LifetimeParam {
+    ast_from_text(&format!("fn f<{}>() {{ }}", lifetime))
+}
+
+pub fn generic_param_list(
+    pats: impl IntoIterator<Item = ast::GenericParam>,
+) -> ast::GenericParamList {
+    let args = pats.into_iter().join(", ");
+    ast_from_text(&format!("fn f<{}>() {{ }}", args))
+}
+
+pub fn visibility_pub_crate() -> ast::Visibility {
+    ast_from_text("pub(crate) struct S")
+}
+
+pub fn visibility_pub() -> ast::Visibility {
+    ast_from_text("pub struct S")
+}
+
+pub fn tuple_field_list(fields: impl IntoIterator<Item = ast::TupleField>) -> ast::TupleFieldList {
+    let fields = fields.into_iter().join(", ");
+    ast_from_text(&format!("struct f({});", fields))
+}
+
+pub fn record_field_list(
+    fields: impl IntoIterator<Item = ast::RecordField>,
+) -> ast::RecordFieldList {
+    let fields = fields.into_iter().join(", ");
+    ast_from_text(&format!("struct f {{ {} }}", fields))
+}
+
+pub fn tuple_field(visibility: Option<ast::Visibility>, ty: ast::Type) -> ast::TupleField {
+    let visibility = match visibility {
+        None => String::new(),
+        Some(it) => format!("{} ", it),
+    };
+    ast_from_text(&format!("struct f({}{});", visibility, ty))
+}
+
+pub fn variant(name: ast::Name, field_list: Option<ast::FieldList>) -> ast::Variant {
+    let field_list = match field_list {
+        None => String::new(),
+        Some(it) => format!("{}", it),
+    };
+    ast_from_text(&format!("enum f {{ {}{} }}", name, field_list))
+}
+
+pub fn fn_(
+    visibility: Option<ast::Visibility>,
+    fn_name: ast::Name,
+    type_params: Option<ast::GenericParamList>,
+    params: ast::ParamList,
+    body: ast::BlockExpr,
+    ret_type: Option<ast::RetType>,
+    is_async: bool,
+) -> ast::Fn {
+    let type_params = match type_params {
+        Some(type_params) => format!("{}", type_params),
+        None => "".into(),
+    };
+    let ret_type = match ret_type {
+        Some(ret_type) => format!("{} ", ret_type),
+        None => "".into(),
+    };
+    let visibility = match visibility {
+        None => String::new(),
+        Some(it) => format!("{} ", it),
+    };
+
+    let async_literal = if is_async { "async " } else { "" };
+
+    ast_from_text(&format!(
+        "{}{}fn {}{}{} {}{}",
+        visibility, async_literal, fn_name, type_params, params, ret_type, body
+    ))
+}
+
+pub fn struct_(
+    visibility: Option<ast::Visibility>,
+    strukt_name: ast::Name,
+    generic_param_list: Option<ast::GenericParamList>,
+    field_list: ast::FieldList,
+) -> ast::Struct {
+    let semicolon = if matches!(field_list, ast::FieldList::TupleFieldList(_)) { ";" } else { "" };
+    let type_params = generic_param_list.map_or_else(String::new, |it| it.to_string());
+    let visibility = match visibility {
+        None => String::new(),
+        Some(it) => format!("{} ", it),
+    };
+
+    ast_from_text(&format!(
+        "{}struct {}{}{}{}",
+        visibility, strukt_name, type_params, field_list, semicolon
+    ))
+}
+
+#[track_caller]
+fn ast_from_text<N: AstNode>(text: &str) -> N {
+    let parse = SourceFile::parse(text);
+    let node = match parse.tree().syntax().descendants().find_map(N::cast) {
+        Some(it) => it,
+        None => {
+            panic!("Failed to make ast node `{}` from text {}", std::any::type_name::<N>(), text)
+        }
+    };
+    let node = node.clone_subtree();
+    assert_eq!(node.syntax().text_range().start(), 0.into());
+    node
+}
+
+pub fn token(kind: SyntaxKind) -> SyntaxToken {
+    tokens::SOURCE_FILE
+        .tree()
+        .syntax()
+        .clone_for_update()
+        .descendants_with_tokens()
+        .filter_map(|it| it.into_token())
+        .find(|it| it.kind() == kind)
+        .unwrap_or_else(|| panic!("unhandled token: {:?}", kind))
+}
+
+pub mod tokens {
+    use once_cell::sync::Lazy;
+
+    use crate::{ast, AstNode, Parse, SourceFile, SyntaxKind::*, SyntaxToken};
+
+    pub(super) static SOURCE_FILE: Lazy<Parse<SourceFile>> = Lazy::new(|| {
+        SourceFile::parse(
+            "const C: <()>::Item = (1 != 1, 2 == 2, 3 < 3, 4 <= 4, 5 > 5, 6 >= 6, !true, *p)\n;\n\n",
+        )
+    });
+
+    pub fn single_space() -> SyntaxToken {
+        SOURCE_FILE
+            .tree()
+            .syntax()
+            .clone_for_update()
+            .descendants_with_tokens()
+            .filter_map(|it| it.into_token())
+            .find(|it| it.kind() == WHITESPACE && it.text() == " ")
+            .unwrap()
+    }
+
+    pub fn whitespace(text: &str) -> SyntaxToken {
+        assert!(text.trim().is_empty());
+        let sf = SourceFile::parse(text).ok().unwrap();
+        sf.syntax().clone_for_update().first_child_or_token().unwrap().into_token().unwrap()
+    }
+
+    pub fn doc_comment(text: &str) -> SyntaxToken {
+        assert!(!text.trim().is_empty());
+        let sf = SourceFile::parse(text).ok().unwrap();
+        sf.syntax().first_child_or_token().unwrap().into_token().unwrap()
+    }
+
+    pub fn literal(text: &str) -> SyntaxToken {
+        assert_eq!(text.trim(), text);
+        let lit: ast::Literal = super::ast_from_text(&format!("fn f() {{ let _ = {}; }}", text));
+        lit.syntax().first_child_or_token().unwrap().into_token().unwrap()
+    }
+
+    pub fn single_newline() -> SyntaxToken {
+        let res = SOURCE_FILE
+            .tree()
+            .syntax()
+            .clone_for_update()
+            .descendants_with_tokens()
+            .filter_map(|it| it.into_token())
+            .find(|it| it.kind() == WHITESPACE && it.text() == "\n")
+            .unwrap();
+        res.detach();
+        res
+    }
+
+    pub fn blank_line() -> SyntaxToken {
+        SOURCE_FILE
+            .tree()
+            .syntax()
+            .clone_for_update()
+            .descendants_with_tokens()
+            .filter_map(|it| it.into_token())
+            .find(|it| it.kind() == WHITESPACE && it.text() == "\n\n")
+            .unwrap()
+    }
+
+    pub struct WsBuilder(SourceFile);
+
+    impl WsBuilder {
+        pub fn new(text: &str) -> WsBuilder {
+            WsBuilder(SourceFile::parse(text).ok().unwrap())
+        }
+        pub fn ws(&self) -> SyntaxToken {
+            self.0.syntax().first_child_or_token().unwrap().into_token().unwrap()
+        }
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ast/node_ext.rs b/src/tools/rust-analyzer/crates/syntax/src/ast/node_ext.rs
new file mode 100644
index 000000000..bb92c51e9
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/ast/node_ext.rs
@@ -0,0 +1,875 @@
+//! Various extension methods to ast Nodes, which are hard to code-generate.
+//! Extensions for various expressions live in a sibling `expr_extensions` module.
+//!
+//! These methods should only do simple, shallow tasks related to the syntax of the node itself.
+
+use std::{borrow::Cow, fmt, iter::successors};
+
+use itertools::Itertools;
+use parser::SyntaxKind;
+use rowan::{GreenNodeData, GreenTokenData};
+
+use crate::{
+    ast::{self, support, AstNode, AstToken, HasAttrs, HasGenericParams, HasName, SyntaxNode},
+    NodeOrToken, SmolStr, SyntaxElement, SyntaxToken, TokenText, T,
+};
+
+impl ast::Lifetime {
+    pub fn text(&self) -> TokenText<'_> {
+        text_of_first_token(self.syntax())
+    }
+}
+
+impl ast::Name {
+    pub fn text(&self) -> TokenText<'_> {
+        text_of_first_token(self.syntax())
+    }
+}
+
+impl ast::NameRef {
+    pub fn text(&self) -> TokenText<'_> {
+        text_of_first_token(self.syntax())
+    }
+
+    pub fn as_tuple_field(&self) -> Option<usize> {
+        self.text().parse().ok()
+    }
+
+    pub fn token_kind(&self) -> SyntaxKind {
+        self.syntax().first_token().map_or(SyntaxKind::ERROR, |it| it.kind())
+    }
+}
+
+fn text_of_first_token(node: &SyntaxNode) -> TokenText<'_> {
+    fn first_token(green_ref: &GreenNodeData) -> &GreenTokenData {
+        green_ref.children().next().and_then(NodeOrToken::into_token).unwrap()
+    }
+
+    match node.green() {
+        Cow::Borrowed(green_ref) => TokenText::borrowed(first_token(green_ref).text()),
+        Cow::Owned(green) => TokenText::owned(first_token(&green).to_owned()),
+    }
+}
+
+impl ast::HasModuleItem for ast::StmtList {}
+
+impl ast::BlockExpr {
+    // FIXME: remove all these methods, they belong to ast::StmtList
+    pub fn statements(&self) -> impl Iterator<Item = ast::Stmt> {
+        self.stmt_list().into_iter().flat_map(|it| it.statements())
+    }
+    pub fn tail_expr(&self) -> Option<ast::Expr> {
+        self.stmt_list()?.tail_expr()
+    }
+}
+
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub enum Macro {
+    MacroRules(ast::MacroRules),
+    MacroDef(ast::MacroDef),
+}
+
+impl From<ast::MacroRules> for Macro {
+    fn from(it: ast::MacroRules) -> Self {
+        Macro::MacroRules(it)
+    }
+}
+
+impl From<ast::MacroDef> for Macro {
+    fn from(it: ast::MacroDef) -> Self {
+        Macro::MacroDef(it)
+    }
+}
+
+impl AstNode for Macro {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        matches!(kind, SyntaxKind::MACRO_RULES | SyntaxKind::MACRO_DEF)
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        let res = match syntax.kind() {
+            SyntaxKind::MACRO_RULES => Macro::MacroRules(ast::MacroRules { syntax }),
+            SyntaxKind::MACRO_DEF => Macro::MacroDef(ast::MacroDef { syntax }),
+            _ => return None,
+        };
+        Some(res)
+    }
+    fn syntax(&self) -> &SyntaxNode {
+        match self {
+            Macro::MacroRules(it) => it.syntax(),
+            Macro::MacroDef(it) => it.syntax(),
+        }
+    }
+}
+
+impl HasName for Macro {
+    fn name(&self) -> Option<ast::Name> {
+        match self {
+            Macro::MacroRules(mac) => mac.name(),
+            Macro::MacroDef(mac) => mac.name(),
+        }
+    }
+}
+
+impl HasAttrs for Macro {}
+
+impl From<ast::AssocItem> for ast::Item {
+    fn from(assoc: ast::AssocItem) -> Self {
+        match assoc {
+            ast::AssocItem::Const(it) => ast::Item::Const(it),
+            ast::AssocItem::Fn(it) => ast::Item::Fn(it),
+            ast::AssocItem::MacroCall(it) => ast::Item::MacroCall(it),
+            ast::AssocItem::TypeAlias(it) => ast::Item::TypeAlias(it),
+        }
+    }
+}
+
+#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+pub enum AttrKind {
+    Inner,
+    Outer,
+}
+
+impl AttrKind {
+    /// Returns `true` if the attr_kind is [`Inner`](Self::Inner).
+    pub fn is_inner(&self) -> bool {
+        matches!(self, Self::Inner)
+    }
+
+    /// Returns `true` if the attr_kind is [`Outer`](Self::Outer).
+    pub fn is_outer(&self) -> bool {
+        matches!(self, Self::Outer)
+    }
+}
+
+impl ast::Attr {
+    pub fn as_simple_atom(&self) -> Option<SmolStr> {
+        let meta = self.meta()?;
+        if meta.eq_token().is_some() || meta.token_tree().is_some() {
+            return None;
+        }
+        self.simple_name()
+    }
+
+    pub fn as_simple_call(&self) -> Option<(SmolStr, ast::TokenTree)> {
+        let tt = self.meta()?.token_tree()?;
+        Some((self.simple_name()?, tt))
+    }
+
+    pub fn simple_name(&self) -> Option<SmolStr> {
+        let path = self.meta()?.path()?;
+        match (path.segment(), path.qualifier()) {
+            (Some(segment), None) => Some(segment.syntax().first_token()?.text().into()),
+            _ => None,
+        }
+    }
+
+    pub fn kind(&self) -> AttrKind {
+        match self.excl_token() {
+            Some(_) => AttrKind::Inner,
+            None => AttrKind::Outer,
+        }
+    }
+
+    pub fn path(&self) -> Option<ast::Path> {
+        self.meta()?.path()
+    }
+
+    pub fn expr(&self) -> Option<ast::Expr> {
+        self.meta()?.expr()
+    }
+
+    pub fn token_tree(&self) -> Option<ast::TokenTree> {
+        self.meta()?.token_tree()
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum PathSegmentKind {
+    Name(ast::NameRef),
+    Type { type_ref: Option<ast::Type>, trait_ref: Option<ast::PathType> },
+    SelfTypeKw,
+    SelfKw,
+    SuperKw,
+    CrateKw,
+}
+
+impl ast::PathSegment {
+    pub fn parent_path(&self) -> ast::Path {
+        self.syntax()
+            .parent()
+            .and_then(ast::Path::cast)
+            .expect("segments are always nested in paths")
+    }
+
+    pub fn crate_token(&self) -> Option<SyntaxToken> {
+        self.name_ref().and_then(|it| it.crate_token())
+    }
+
+    pub fn self_token(&self) -> Option<SyntaxToken> {
+        self.name_ref().and_then(|it| it.self_token())
+    }
+
+    pub fn self_type_token(&self) -> Option<SyntaxToken> {
+        self.name_ref().and_then(|it| it.Self_token())
+    }
+
+    pub fn super_token(&self) -> Option<SyntaxToken> {
+        self.name_ref().and_then(|it| it.super_token())
+    }
+
+    pub fn kind(&self) -> Option<PathSegmentKind> {
+        let res = if let Some(name_ref) = self.name_ref() {
+            match name_ref.token_kind() {
+                T![Self] => PathSegmentKind::SelfTypeKw,
+                T![self] => PathSegmentKind::SelfKw,
+                T![super] => PathSegmentKind::SuperKw,
+                T![crate] => PathSegmentKind::CrateKw,
+                _ => PathSegmentKind::Name(name_ref),
+            }
+        } else {
+            match self.syntax().first_child_or_token()?.kind() {
+                T![<] => {
+                    // <T> or <T as Trait>
+                    // T is any TypeRef, Trait has to be a PathType
+                    let mut type_refs =
+                        self.syntax().children().filter(|node| ast::Type::can_cast(node.kind()));
+                    let type_ref = type_refs.next().and_then(ast::Type::cast);
+                    let trait_ref = type_refs.next().and_then(ast::PathType::cast);
+                    PathSegmentKind::Type { type_ref, trait_ref }
+                }
+                _ => return None,
+            }
+        };
+        Some(res)
+    }
+}
+
+impl ast::Path {
+    pub fn parent_path(&self) -> Option<ast::Path> {
+        self.syntax().parent().and_then(ast::Path::cast)
+    }
+
+    pub fn as_single_segment(&self) -> Option<ast::PathSegment> {
+        match self.qualifier() {
+            Some(_) => None,
+            None => self.segment(),
+        }
+    }
+
+    pub fn as_single_name_ref(&self) -> Option<ast::NameRef> {
+        match self.qualifier() {
+            Some(_) => None,
+            None => self.segment()?.name_ref(),
+        }
+    }
+
+    pub fn first_qualifier_or_self(&self) -> ast::Path {
+        successors(Some(self.clone()), ast::Path::qualifier).last().unwrap()
+    }
+
+    pub fn first_segment(&self) -> Option<ast::PathSegment> {
+        self.first_qualifier_or_self().segment()
+    }
+
+    pub fn segments(&self) -> impl Iterator<Item = ast::PathSegment> + Clone {
+        successors(self.first_segment(), |p| {
+            p.parent_path().parent_path().and_then(|p| p.segment())
+        })
+    }
+
+    pub fn qualifiers(&self) -> impl Iterator<Item = ast::Path> + Clone {
+        successors(self.qualifier(), |p| p.qualifier())
+    }
+
+    pub fn top_path(&self) -> ast::Path {
+        let mut this = self.clone();
+        while let Some(path) = this.parent_path() {
+            this = path;
+        }
+        this
+    }
+}
+
+impl ast::Use {
+    pub fn is_simple_glob(&self) -> bool {
+        self.use_tree().map_or(false, |use_tree| {
+            use_tree.use_tree_list().is_none() && use_tree.star_token().is_some()
+        })
+    }
+}
+
+impl ast::UseTree {
+    pub fn is_simple_path(&self) -> bool {
+        self.use_tree_list().is_none() && self.star_token().is_none()
+    }
+}
+
+impl ast::UseTreeList {
+    pub fn parent_use_tree(&self) -> ast::UseTree {
+        self.syntax()
+            .parent()
+            .and_then(ast::UseTree::cast)
+            .expect("UseTreeLists are always nested in UseTrees")
+    }
+
+    pub fn has_inner_comment(&self) -> bool {
+        self.syntax()
+            .children_with_tokens()
+            .filter_map(|it| it.into_token())
+            .find_map(ast::Comment::cast)
+            .is_some()
+    }
+}
+
+impl ast::Impl {
+    pub fn self_ty(&self) -> Option<ast::Type> {
+        match self.target() {
+            (Some(t), None) | (_, Some(t)) => Some(t),
+            _ => None,
+        }
+    }
+
+    pub fn trait_(&self) -> Option<ast::Type> {
+        match self.target() {
+            (Some(t), Some(_)) => Some(t),
+            _ => None,
+        }
+    }
+
+    fn target(&self) -> (Option<ast::Type>, Option<ast::Type>) {
+        let mut types = support::children(self.syntax());
+        let first = types.next();
+        let second = types.next();
+        (first, second)
+    }
+
+    pub fn for_trait_name_ref(name_ref: &ast::NameRef) -> Option<ast::Impl> {
+        let this = name_ref.syntax().ancestors().find_map(ast::Impl::cast)?;
+        if this.trait_()?.syntax().text_range().start() == name_ref.syntax().text_range().start() {
+            Some(this)
+        } else {
+            None
+        }
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum StructKind {
+    Record(ast::RecordFieldList),
+    Tuple(ast::TupleFieldList),
+    Unit,
+}
+
+impl StructKind {
+    fn from_node<N: AstNode>(node: &N) -> StructKind {
+        if let Some(nfdl) = support::child::<ast::RecordFieldList>(node.syntax()) {
+            StructKind::Record(nfdl)
+        } else if let Some(pfl) = support::child::<ast::TupleFieldList>(node.syntax()) {
+            StructKind::Tuple(pfl)
+        } else {
+            StructKind::Unit
+        }
+    }
+}
+
+impl ast::Struct {
+    pub fn kind(&self) -> StructKind {
+        StructKind::from_node(self)
+    }
+}
+
+impl ast::RecordExprField {
+    pub fn for_field_name(field_name: &ast::NameRef) -> Option<ast::RecordExprField> {
+        let candidate = Self::for_name_ref(field_name)?;
+        if candidate.field_name().as_ref() == Some(field_name) {
+            Some(candidate)
+        } else {
+            None
+        }
+    }
+
+    pub fn for_name_ref(name_ref: &ast::NameRef) -> Option<ast::RecordExprField> {
+        let syn = name_ref.syntax();
+        syn.parent()
+            .and_then(ast::RecordExprField::cast)
+            .or_else(|| syn.ancestors().nth(4).and_then(ast::RecordExprField::cast))
+    }
+
+    /// Deals with field init shorthand
+    pub fn field_name(&self) -> Option<ast::NameRef> {
+        if let Some(name_ref) = self.name_ref() {
+            return Some(name_ref);
+        }
+        if let ast::Expr::PathExpr(expr) = self.expr()? {
+            let path = expr.path()?;
+            let segment = path.segment()?;
+            let name_ref = segment.name_ref()?;
+            if path.qualifier().is_none() {
+                return Some(name_ref);
+            }
+        }
+        None
+    }
+}
+
+#[derive(Debug, Clone)]
+pub enum NameLike {
+    NameRef(ast::NameRef),
+    Name(ast::Name),
+    Lifetime(ast::Lifetime),
+}
+
+impl NameLike {
+    pub fn as_name_ref(&self) -> Option<&ast::NameRef> {
+        match self {
+            NameLike::NameRef(name_ref) => Some(name_ref),
+            _ => None,
+        }
+    }
+    pub fn as_lifetime(&self) -> Option<&ast::Lifetime> {
+        match self {
+            NameLike::Lifetime(lifetime) => Some(lifetime),
+            _ => None,
+        }
+    }
+    pub fn text(&self) -> TokenText<'_> {
+        match self {
+            NameLike::NameRef(name_ref) => name_ref.text(),
+            NameLike::Name(name) => name.text(),
+            NameLike::Lifetime(lifetime) => lifetime.text(),
+        }
+    }
+}
+
+impl ast::AstNode for NameLike {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        matches!(kind, SyntaxKind::NAME | SyntaxKind::NAME_REF | SyntaxKind::LIFETIME)
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        let res = match syntax.kind() {
+            SyntaxKind::NAME => NameLike::Name(ast::Name { syntax }),
+            SyntaxKind::NAME_REF => NameLike::NameRef(ast::NameRef { syntax }),
+            SyntaxKind::LIFETIME => NameLike::Lifetime(ast::Lifetime { syntax }),
+            _ => return None,
+        };
+        Some(res)
+    }
+    fn syntax(&self) -> &SyntaxNode {
+        match self {
+            NameLike::NameRef(it) => it.syntax(),
+            NameLike::Name(it) => it.syntax(),
+            NameLike::Lifetime(it) => it.syntax(),
+        }
+    }
+}
+
+const _: () = {
+    use ast::{Lifetime, Name, NameRef};
+    stdx::impl_from!(NameRef, Name, Lifetime for NameLike);
+};
+
+#[derive(Debug, Clone, PartialEq)]
+pub enum NameOrNameRef {
+    Name(ast::Name),
+    NameRef(ast::NameRef),
+}
+
+impl fmt::Display for NameOrNameRef {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            NameOrNameRef::Name(it) => fmt::Display::fmt(it, f),
+            NameOrNameRef::NameRef(it) => fmt::Display::fmt(it, f),
+        }
+    }
+}
+
+impl NameOrNameRef {
+    pub fn text(&self) -> TokenText<'_> {
+        match self {
+            NameOrNameRef::Name(name) => name.text(),
+            NameOrNameRef::NameRef(name_ref) => name_ref.text(),
+        }
+    }
+}
+
+impl ast::RecordPatField {
+    pub fn for_field_name_ref(field_name: &ast::NameRef) -> Option<ast::RecordPatField> {
+        let candidate = field_name.syntax().parent().and_then(ast::RecordPatField::cast)?;
+        match candidate.field_name()? {
+            NameOrNameRef::NameRef(name_ref) if name_ref == *field_name => Some(candidate),
+            _ => None,
+        }
+    }
+
+    pub fn for_field_name(field_name: &ast::Name) -> Option<ast::RecordPatField> {
+        let candidate =
+            field_name.syntax().ancestors().nth(2).and_then(ast::RecordPatField::cast)?;
+        match candidate.field_name()? {
+            NameOrNameRef::Name(name) if name == *field_name => Some(candidate),
+            _ => None,
+        }
+    }
+
+    pub fn parent_record_pat(&self) -> ast::RecordPat {
+        self.syntax().ancestors().find_map(ast::RecordPat::cast).unwrap()
+    }
+
+    /// Deals with field init shorthand
+    pub fn field_name(&self) -> Option<NameOrNameRef> {
+        if let Some(name_ref) = self.name_ref() {
+            return Some(NameOrNameRef::NameRef(name_ref));
+        }
+        match self.pat() {
+            Some(ast::Pat::IdentPat(pat)) => {
+                let name = pat.name()?;
+                Some(NameOrNameRef::Name(name))
+            }
+            Some(ast::Pat::BoxPat(pat)) => match pat.pat() {
+                Some(ast::Pat::IdentPat(pat)) => {
+                    let name = pat.name()?;
+                    Some(NameOrNameRef::Name(name))
+                }
+                _ => None,
+            },
+            _ => None,
+        }
+    }
+}
+
+impl ast::Variant {
+    pub fn parent_enum(&self) -> ast::Enum {
+        self.syntax()
+            .parent()
+            .and_then(|it| it.parent())
+            .and_then(ast::Enum::cast)
+            .expect("EnumVariants are always nested in Enums")
+    }
+    pub fn kind(&self) -> StructKind {
+        StructKind::from_node(self)
+    }
+}
+
+impl ast::Item {
+    pub fn generic_param_list(&self) -> Option<ast::GenericParamList> {
+        ast::AnyHasGenericParams::cast(self.syntax().clone())?.generic_param_list()
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum FieldKind {
+    Name(ast::NameRef),
+    Index(SyntaxToken),
+}
+
+impl ast::FieldExpr {
+    pub fn index_token(&self) -> Option<SyntaxToken> {
+        self.syntax
+            .children_with_tokens()
+            // FIXME: Accepting floats here to reject them in validation later
+            .find(|c| c.kind() == SyntaxKind::INT_NUMBER || c.kind() == SyntaxKind::FLOAT_NUMBER)
+            .as_ref()
+            .and_then(SyntaxElement::as_token)
+            .cloned()
+    }
+
+    pub fn field_access(&self) -> Option<FieldKind> {
+        match self.name_ref() {
+            Some(nr) => Some(FieldKind::Name(nr)),
+            None => self.index_token().map(FieldKind::Index),
+        }
+    }
+}
+
+pub struct SlicePatComponents {
+    pub prefix: Vec<ast::Pat>,
+    pub slice: Option<ast::Pat>,
+    pub suffix: Vec<ast::Pat>,
+}
+
+impl ast::SlicePat {
+    pub fn components(&self) -> SlicePatComponents {
+        let mut args = self.pats().peekable();
+        let prefix = args
+            .peeking_take_while(|p| match p {
+                ast::Pat::RestPat(_) => false,
+                ast::Pat::IdentPat(bp) => !matches!(bp.pat(), Some(ast::Pat::RestPat(_))),
+                ast::Pat::RefPat(rp) => match rp.pat() {
+                    Some(ast::Pat::RestPat(_)) => false,
+                    Some(ast::Pat::IdentPat(bp)) => !matches!(bp.pat(), Some(ast::Pat::RestPat(_))),
+                    _ => true,
+                },
+                _ => true,
+            })
+            .collect();
+        let slice = args.next();
+        let suffix = args.collect();
+
+        SlicePatComponents { prefix, slice, suffix }
+    }
+}
+
+impl ast::IdentPat {
+    pub fn is_simple_ident(&self) -> bool {
+        self.at_token().is_none()
+            && self.mut_token().is_none()
+            && self.ref_token().is_none()
+            && self.pat().is_none()
+    }
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+pub enum SelfParamKind {
+    /// self
+    Owned,
+    /// &self
+    Ref,
+    /// &mut self
+    MutRef,
+}
+
+impl ast::SelfParam {
+    pub fn kind(&self) -> SelfParamKind {
+        if self.amp_token().is_some() {
+            if self.mut_token().is_some() {
+                SelfParamKind::MutRef
+            } else {
+                SelfParamKind::Ref
+            }
+        } else {
+            SelfParamKind::Owned
+        }
+    }
+}
+
+#[derive(Clone, Debug, PartialEq, Eq, Hash)]
+pub enum TypeBoundKind {
+    /// Trait
+    PathType(ast::PathType),
+    /// for<'a> ...
+    ForType(ast::ForType),
+    /// 'a
+    Lifetime(ast::Lifetime),
+}
+
+impl ast::TypeBound {
+    pub fn kind(&self) -> TypeBoundKind {
+        if let Some(path_type) = support::children(self.syntax()).next() {
+            TypeBoundKind::PathType(path_type)
+        } else if let Some(for_type) = support::children(self.syntax()).next() {
+            TypeBoundKind::ForType(for_type)
+        } else if let Some(lifetime) = self.lifetime() {
+            TypeBoundKind::Lifetime(lifetime)
+        } else {
+            unreachable!()
+        }
+    }
+}
+
+#[derive(Debug, Clone)]
+pub enum TypeOrConstParam {
+    Type(ast::TypeParam),
+    Const(ast::ConstParam),
+}
+
+impl TypeOrConstParam {
+    pub fn name(&self) -> Option<ast::Name> {
+        match self {
+            TypeOrConstParam::Type(x) => x.name(),
+            TypeOrConstParam::Const(x) => x.name(),
+        }
+    }
+}
+
+pub enum VisibilityKind {
+    In(ast::Path),
+    PubCrate,
+    PubSuper,
+    PubSelf,
+    Pub,
+}
+
+impl ast::Visibility {
+    pub fn kind(&self) -> VisibilityKind {
+        match self.path() {
+            Some(path) => {
+                if let Some(segment) =
+                    path.as_single_segment().filter(|it| it.coloncolon_token().is_none())
+                {
+                    if segment.crate_token().is_some() {
+                        return VisibilityKind::PubCrate;
+                    } else if segment.super_token().is_some() {
+                        return VisibilityKind::PubSuper;
+                    } else if segment.self_token().is_some() {
+                        return VisibilityKind::PubSelf;
+                    }
+                }
+                VisibilityKind::In(path)
+            }
+            None => VisibilityKind::Pub,
+        }
+    }
+}
+
+impl ast::LifetimeParam {
+    pub fn lifetime_bounds(&self) -> impl Iterator<Item = SyntaxToken> {
+        self.syntax()
+            .children_with_tokens()
+            .filter_map(|it| it.into_token())
+            .skip_while(|x| x.kind() != T![:])
+            .filter(|it| it.kind() == T![lifetime_ident])
+    }
+}
+
+impl ast::Module {
+    /// Returns the parent ast::Module, this is different than the semantic parent in that this only
+    /// considers parent declarations in the AST
+    pub fn parent(&self) -> Option<ast::Module> {
+        self.syntax().ancestors().nth(2).and_then(ast::Module::cast)
+    }
+}
+
+impl ast::RangePat {
+    pub fn start(&self) -> Option<ast::Pat> {
+        self.syntax()
+            .children_with_tokens()
+            .take_while(|it| !(it.kind() == T![..] || it.kind() == T![..=]))
+            .filter_map(|it| it.into_node())
+            .find_map(ast::Pat::cast)
+    }
+
+    pub fn end(&self) -> Option<ast::Pat> {
+        self.syntax()
+            .children_with_tokens()
+            .skip_while(|it| !(it.kind() == T![..] || it.kind() == T![..=]))
+            .filter_map(|it| it.into_node())
+            .find_map(ast::Pat::cast)
+    }
+}
+
+impl ast::TokenTree {
+    pub fn token_trees_and_tokens(
+        &self,
+    ) -> impl Iterator<Item = NodeOrToken<ast::TokenTree, SyntaxToken>> {
+        self.syntax().children_with_tokens().filter_map(|not| match not {
+            NodeOrToken::Node(node) => ast::TokenTree::cast(node).map(NodeOrToken::Node),
+            NodeOrToken::Token(t) => Some(NodeOrToken::Token(t)),
+        })
+    }
+
+    pub fn left_delimiter_token(&self) -> Option<SyntaxToken> {
+        self.syntax()
+            .first_child_or_token()?
+            .into_token()
+            .filter(|it| matches!(it.kind(), T!['{'] | T!['('] | T!['[']))
+    }
+
+    pub fn right_delimiter_token(&self) -> Option<SyntaxToken> {
+        self.syntax()
+            .last_child_or_token()?
+            .into_token()
+            .filter(|it| matches!(it.kind(), T!['}'] | T![')'] | T![']']))
+    }
+
+    pub fn parent_meta(&self) -> Option<ast::Meta> {
+        self.syntax().parent().and_then(ast::Meta::cast)
+    }
+}
+
+impl ast::Meta {
+    pub fn parent_attr(&self) -> Option<ast::Attr> {
+        self.syntax().parent().and_then(ast::Attr::cast)
+    }
+}
+
+impl ast::GenericArgList {
+    pub fn lifetime_args(&self) -> impl Iterator<Item = ast::LifetimeArg> {
+        self.generic_args().filter_map(|arg| match arg {
+            ast::GenericArg::LifetimeArg(it) => Some(it),
+            _ => None,
+        })
+    }
+}
+
+impl ast::GenericParamList {
+    pub fn lifetime_params(&self) -> impl Iterator<Item = ast::LifetimeParam> {
+        self.generic_params().filter_map(|param| match param {
+            ast::GenericParam::LifetimeParam(it) => Some(it),
+            ast::GenericParam::TypeParam(_) | ast::GenericParam::ConstParam(_) => None,
+        })
+    }
+    pub fn type_or_const_params(&self) -> impl Iterator<Item = ast::TypeOrConstParam> {
+        self.generic_params().filter_map(|param| match param {
+            ast::GenericParam::TypeParam(it) => Some(ast::TypeOrConstParam::Type(it)),
+            ast::GenericParam::LifetimeParam(_) => None,
+            ast::GenericParam::ConstParam(it) => Some(ast::TypeOrConstParam::Const(it)),
+        })
+    }
+}
+
+impl ast::ForExpr {
+    pub fn iterable(&self) -> Option<ast::Expr> {
+        // If the iterable is a BlockExpr, check if the body is missing.
+        // If it is assume the iterable is the expression that is missing instead.
+        let mut exprs = support::children(self.syntax());
+        let first = exprs.next();
+        match first {
+            Some(ast::Expr::BlockExpr(_)) => exprs.next().and(first),
+            first => first,
+        }
+    }
+}
+
+impl ast::HasLoopBody for ast::ForExpr {
+    fn loop_body(&self) -> Option<ast::BlockExpr> {
+        let mut exprs = support::children(self.syntax());
+        let first = exprs.next();
+        let second = exprs.next();
+        second.or(first)
+    }
+}
+
+impl ast::WhileExpr {
+    pub fn condition(&self) -> Option<ast::Expr> {
+        // If the condition is a BlockExpr, check if the body is missing.
+        // If it is assume the condition is the expression that is missing instead.
+        let mut exprs = support::children(self.syntax());
+        let first = exprs.next();
+        match first {
+            Some(ast::Expr::BlockExpr(_)) => exprs.next().and(first),
+            first => first,
+        }
+    }
+}
+
+impl ast::HasLoopBody for ast::WhileExpr {
+    fn loop_body(&self) -> Option<ast::BlockExpr> {
+        let mut exprs = support::children(self.syntax());
+        let first = exprs.next();
+        let second = exprs.next();
+        second.or(first)
+    }
+}
+
+impl ast::HasAttrs for ast::AnyHasDocComments {}
+
+impl From<ast::Adt> for ast::Item {
+    fn from(it: ast::Adt) -> Self {
+        match it {
+            ast::Adt::Enum(it) => ast::Item::Enum(it),
+            ast::Adt::Struct(it) => ast::Item::Struct(it),
+            ast::Adt::Union(it) => ast::Item::Union(it),
+        }
+    }
+}
+
+impl ast::IfExpr {
+    pub fn condition(&self) -> Option<ast::Expr> {
+        support::child(&self.syntax)
+    }
+}
+
+impl ast::MatchGuard {
+    pub fn condition(&self) -> Option<ast::Expr> {
+        support::child(&self.syntax)
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ast/operators.rs b/src/tools/rust-analyzer/crates/syntax/src/ast/operators.rs
new file mode 100644
index 000000000..a687ba0b7
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/ast/operators.rs
@@ -0,0 +1,122 @@
+//! Defines a bunch of data-less enums for unary and binary operators.
+//!
+//! Types here don't know about AST, this allows re-using them for both AST and
+//! HIR.
+use std::fmt;
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+pub enum RangeOp {
+    /// `..`
+    Exclusive,
+    /// `..=`
+    Inclusive,
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+pub enum UnaryOp {
+    /// `*`
+    Deref,
+    /// `!`
+    Not,
+    /// `-`
+    Neg,
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+pub enum BinaryOp {
+    LogicOp(LogicOp),
+    ArithOp(ArithOp),
+    CmpOp(CmpOp),
+    Assignment { op: Option<ArithOp> },
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+pub enum LogicOp {
+    And,
+    Or,
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+pub enum CmpOp {
+    Eq { negated: bool },
+    Ord { ordering: Ordering, strict: bool },
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+pub enum Ordering {
+    Less,
+    Greater,
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+pub enum ArithOp {
+    Add,
+    Mul,
+    Sub,
+    Div,
+    Rem,
+    Shl,
+    Shr,
+    BitXor,
+    BitOr,
+    BitAnd,
+}
+
+impl fmt::Display for LogicOp {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let res = match self {
+            LogicOp::And => "&&",
+            LogicOp::Or => "||",
+        };
+        f.write_str(res)
+    }
+}
+
+impl fmt::Display for ArithOp {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let res = match self {
+            ArithOp::Add => "+",
+            ArithOp::Mul => "*",
+            ArithOp::Sub => "-",
+            ArithOp::Div => "/",
+            ArithOp::Rem => "%",
+            ArithOp::Shl => "<<",
+            ArithOp::Shr => ">>",
+            ArithOp::BitXor => "^",
+            ArithOp::BitOr => "|",
+            ArithOp::BitAnd => "&",
+        };
+        f.write_str(res)
+    }
+}
+
+impl fmt::Display for CmpOp {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let res = match self {
+            CmpOp::Eq { negated: false } => "==",
+            CmpOp::Eq { negated: true } => "!=",
+            CmpOp::Ord { ordering: Ordering::Less, strict: false } => "<=",
+            CmpOp::Ord { ordering: Ordering::Less, strict: true } => "<",
+            CmpOp::Ord { ordering: Ordering::Greater, strict: false } => ">=",
+            CmpOp::Ord { ordering: Ordering::Greater, strict: true } => ">",
+        };
+        f.write_str(res)
+    }
+}
+
+impl fmt::Display for BinaryOp {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            BinaryOp::LogicOp(op) => fmt::Display::fmt(op, f),
+            BinaryOp::ArithOp(op) => fmt::Display::fmt(op, f),
+            BinaryOp::CmpOp(op) => fmt::Display::fmt(op, f),
+            BinaryOp::Assignment { op } => {
+                f.write_str("=")?;
+                if let Some(op) = op {
+                    fmt::Display::fmt(op, f)?;
+                }
+                Ok(())
+            }
+        }
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ast/token_ext.rs b/src/tools/rust-analyzer/crates/syntax/src/ast/token_ext.rs
new file mode 100644
index 000000000..28976d837
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/ast/token_ext.rs
@@ -0,0 +1,472 @@
+//! There are many AstNodes, but only a few tokens, so we hand-write them here.
+
+use std::borrow::Cow;
+
+use rustc_lexer::unescape::{unescape_byte, unescape_char, unescape_literal, Mode};
+
+use crate::{
+    ast::{self, AstToken},
+    TextRange, TextSize,
+};
+
+impl ast::Comment {
+    pub fn kind(&self) -> CommentKind {
+        CommentKind::from_text(self.text())
+    }
+
+    pub fn is_doc(&self) -> bool {
+        self.kind().doc.is_some()
+    }
+
+    pub fn is_inner(&self) -> bool {
+        self.kind().doc == Some(CommentPlacement::Inner)
+    }
+
+    pub fn is_outer(&self) -> bool {
+        self.kind().doc == Some(CommentPlacement::Outer)
+    }
+
+    pub fn prefix(&self) -> &'static str {
+        let &(prefix, _kind) = CommentKind::BY_PREFIX
+            .iter()
+            .find(|&(prefix, kind)| self.kind() == *kind && self.text().starts_with(prefix))
+            .unwrap();
+        prefix
+    }
+
+    /// Returns the textual content of a doc comment node as a single string with prefix and suffix
+    /// removed.
+    pub fn doc_comment(&self) -> Option<&str> {
+        let kind = self.kind();
+        match kind {
+            CommentKind { shape, doc: Some(_) } => {
+                let prefix = kind.prefix();
+                let text = &self.text()[prefix.len()..];
+                let text = if shape == CommentShape::Block {
+                    text.strip_suffix("*/").unwrap_or(text)
+                } else {
+                    text
+                };
+                Some(text)
+            }
+            _ => None,
+        }
+    }
+}
+
+#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+pub struct CommentKind {
+    pub shape: CommentShape,
+    pub doc: Option<CommentPlacement>,
+}
+
+#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+pub enum CommentShape {
+    Line,
+    Block,
+}
+
+impl CommentShape {
+    pub fn is_line(self) -> bool {
+        self == CommentShape::Line
+    }
+
+    pub fn is_block(self) -> bool {
+        self == CommentShape::Block
+    }
+}
+
+#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+pub enum CommentPlacement {
+    Inner,
+    Outer,
+}
+
+impl CommentKind {
+    const BY_PREFIX: [(&'static str, CommentKind); 9] = [
+        ("/**/", CommentKind { shape: CommentShape::Block, doc: None }),
+        ("/***", CommentKind { shape: CommentShape::Block, doc: None }),
+        ("////", CommentKind { shape: CommentShape::Line, doc: None }),
+        ("///", CommentKind { shape: CommentShape::Line, doc: Some(CommentPlacement::Outer) }),
+        ("//!", CommentKind { shape: CommentShape::Line, doc: Some(CommentPlacement::Inner) }),
+        ("/**", CommentKind { shape: CommentShape::Block, doc: Some(CommentPlacement::Outer) }),
+        ("/*!", CommentKind { shape: CommentShape::Block, doc: Some(CommentPlacement::Inner) }),
+        ("//", CommentKind { shape: CommentShape::Line, doc: None }),
+        ("/*", CommentKind { shape: CommentShape::Block, doc: None }),
+    ];
+
+    pub(crate) fn from_text(text: &str) -> CommentKind {
+        let &(_prefix, kind) = CommentKind::BY_PREFIX
+            .iter()
+            .find(|&(prefix, _kind)| text.starts_with(prefix))
+            .unwrap();
+        kind
+    }
+
+    pub fn prefix(&self) -> &'static str {
+        let &(prefix, _) =
+            CommentKind::BY_PREFIX.iter().rev().find(|(_, kind)| kind == self).unwrap();
+        prefix
+    }
+}
+
+impl ast::Whitespace {
+    pub fn spans_multiple_lines(&self) -> bool {
+        let text = self.text();
+        text.find('\n').map_or(false, |idx| text[idx + 1..].contains('\n'))
+    }
+}
+
+pub struct QuoteOffsets {
+    pub quotes: (TextRange, TextRange),
+    pub contents: TextRange,
+}
+
+impl QuoteOffsets {
+    fn new(literal: &str) -> Option<QuoteOffsets> {
+        let left_quote = literal.find('"')?;
+        let right_quote = literal.rfind('"')?;
+        if left_quote == right_quote {
+            // `literal` only contains one quote
+            return None;
+        }
+
+        let start = TextSize::from(0);
+        let left_quote = TextSize::try_from(left_quote).unwrap() + TextSize::of('"');
+        let right_quote = TextSize::try_from(right_quote).unwrap();
+        let end = TextSize::of(literal);
+
+        let res = QuoteOffsets {
+            quotes: (TextRange::new(start, left_quote), TextRange::new(right_quote, end)),
+            contents: TextRange::new(left_quote, right_quote),
+        };
+        Some(res)
+    }
+}
+
+pub trait IsString: AstToken {
+    fn quote_offsets(&self) -> Option<QuoteOffsets> {
+        let text = self.text();
+        let offsets = QuoteOffsets::new(text)?;
+        let o = self.syntax().text_range().start();
+        let offsets = QuoteOffsets {
+            quotes: (offsets.quotes.0 + o, offsets.quotes.1 + o),
+            contents: offsets.contents + o,
+        };
+        Some(offsets)
+    }
+    fn text_range_between_quotes(&self) -> Option<TextRange> {
+        self.quote_offsets().map(|it| it.contents)
+    }
+    fn open_quote_text_range(&self) -> Option<TextRange> {
+        self.quote_offsets().map(|it| it.quotes.0)
+    }
+    fn close_quote_text_range(&self) -> Option<TextRange> {
+        self.quote_offsets().map(|it| it.quotes.1)
+    }
+    fn escaped_char_ranges(
+        &self,
+        cb: &mut dyn FnMut(TextRange, Result<char, rustc_lexer::unescape::EscapeError>),
+    ) {
+        let text_range_no_quotes = match self.text_range_between_quotes() {
+            Some(it) => it,
+            None => return,
+        };
+
+        let start = self.syntax().text_range().start();
+        let text = &self.text()[text_range_no_quotes - start];
+        let offset = text_range_no_quotes.start() - start;
+
+        unescape_literal(text, Mode::Str, &mut |range, unescaped_char| {
+            let text_range =
+                TextRange::new(range.start.try_into().unwrap(), range.end.try_into().unwrap());
+            cb(text_range + offset, unescaped_char);
+        });
+    }
+}
+
+impl IsString for ast::String {}
+
+impl ast::String {
+    pub fn is_raw(&self) -> bool {
+        self.text().starts_with('r')
+    }
+    pub fn map_range_up(&self, range: TextRange) -> Option<TextRange> {
+        let contents_range = self.text_range_between_quotes()?;
+        assert!(TextRange::up_to(contents_range.len()).contains_range(range));
+        Some(range + contents_range.start())
+    }
+
+    pub fn value(&self) -> Option<Cow<'_, str>> {
+        if self.is_raw() {
+            let text = self.text();
+            let text =
+                &text[self.text_range_between_quotes()? - self.syntax().text_range().start()];
+            return Some(Cow::Borrowed(text));
+        }
+
+        let text = self.text();
+        let text = &text[self.text_range_between_quotes()? - self.syntax().text_range().start()];
+
+        let mut buf = String::new();
+        let mut text_iter = text.chars();
+        let mut has_error = false;
+        unescape_literal(text, Mode::Str, &mut |char_range, unescaped_char| match (
+            unescaped_char,
+            buf.capacity() == 0,
+        ) {
+            (Ok(c), false) => buf.push(c),
+            (Ok(c), true) if char_range.len() == 1 && Some(c) == text_iter.next() => (),
+            (Ok(c), true) => {
+                buf.reserve_exact(text.len());
+                buf.push_str(&text[..char_range.start]);
+                buf.push(c);
+            }
+            (Err(_), _) => has_error = true,
+        });
+
+        match (has_error, buf.capacity() == 0) {
+            (true, _) => None,
+            (false, true) => Some(Cow::Borrowed(text)),
+            (false, false) => Some(Cow::Owned(buf)),
+        }
+    }
+}
+
+impl IsString for ast::ByteString {}
+
+impl ast::ByteString {
+    pub fn is_raw(&self) -> bool {
+        self.text().starts_with("br")
+    }
+
+    pub fn value(&self) -> Option<Cow<'_, [u8]>> {
+        if self.is_raw() {
+            let text = self.text();
+            let text =
+                &text[self.text_range_between_quotes()? - self.syntax().text_range().start()];
+            return Some(Cow::Borrowed(text.as_bytes()));
+        }
+
+        let text = self.text();
+        let text = &text[self.text_range_between_quotes()? - self.syntax().text_range().start()];
+
+        let mut buf: Vec<u8> = Vec::new();
+        let mut text_iter = text.chars();
+        let mut has_error = false;
+        unescape_literal(text, Mode::ByteStr, &mut |char_range, unescaped_char| match (
+            unescaped_char,
+            buf.capacity() == 0,
+        ) {
+            (Ok(c), false) => buf.push(c as u8),
+            (Ok(c), true) if char_range.len() == 1 && Some(c) == text_iter.next() => (),
+            (Ok(c), true) => {
+                buf.reserve_exact(text.len());
+                buf.extend_from_slice(text[..char_range.start].as_bytes());
+                buf.push(c as u8);
+            }
+            (Err(_), _) => has_error = true,
+        });
+
+        match (has_error, buf.capacity() == 0) {
+            (true, _) => None,
+            (false, true) => Some(Cow::Borrowed(text.as_bytes())),
+            (false, false) => Some(Cow::Owned(buf)),
+        }
+    }
+}
+
+impl ast::IntNumber {
+    pub fn radix(&self) -> Radix {
+        match self.text().get(..2).unwrap_or_default() {
+            "0b" => Radix::Binary,
+            "0o" => Radix::Octal,
+            "0x" => Radix::Hexadecimal,
+            _ => Radix::Decimal,
+        }
+    }
+
+    pub fn split_into_parts(&self) -> (&str, &str, &str) {
+        let radix = self.radix();
+        let (prefix, mut text) = self.text().split_at(radix.prefix_len());
+
+        let is_suffix_start: fn(&(usize, char)) -> bool = match radix {
+            Radix::Hexadecimal => |(_, c)| matches!(c, 'g'..='z' | 'G'..='Z'),
+            _ => |(_, c)| c.is_ascii_alphabetic(),
+        };
+
+        let mut suffix = "";
+        if let Some((suffix_start, _)) = text.char_indices().find(is_suffix_start) {
+            let (text2, suffix2) = text.split_at(suffix_start);
+            text = text2;
+            suffix = suffix2;
+        };
+
+        (prefix, text, suffix)
+    }
+
+    pub fn value(&self) -> Option<u128> {
+        let (_, text, _) = self.split_into_parts();
+        let value = u128::from_str_radix(&text.replace('_', ""), self.radix() as u32).ok()?;
+        Some(value)
+    }
+
+    pub fn suffix(&self) -> Option<&str> {
+        let (_, _, suffix) = self.split_into_parts();
+        if suffix.is_empty() {
+            None
+        } else {
+            Some(suffix)
+        }
+    }
+
+    pub fn float_value(&self) -> Option<f64> {
+        let (_, text, _) = self.split_into_parts();
+        text.parse::<f64>().ok()
+    }
+}
+
+impl ast::FloatNumber {
+    pub fn split_into_parts(&self) -> (&str, &str) {
+        let text = self.text();
+        let mut float_text = self.text();
+        let mut suffix = "";
+        let mut indices = text.char_indices();
+        if let Some((mut suffix_start, c)) = indices.by_ref().find(|(_, c)| c.is_ascii_alphabetic())
+        {
+            if c == 'e' || c == 'E' {
+                if let Some(suffix_start_tuple) = indices.find(|(_, c)| c.is_ascii_alphabetic()) {
+                    suffix_start = suffix_start_tuple.0;
+
+                    float_text = &text[..suffix_start];
+                    suffix = &text[suffix_start..];
+                }
+            } else {
+                float_text = &text[..suffix_start];
+                suffix = &text[suffix_start..];
+            }
+        }
+
+        (float_text, suffix)
+    }
+
+    pub fn suffix(&self) -> Option<&str> {
+        let (_, suffix) = self.split_into_parts();
+        if suffix.is_empty() {
+            None
+        } else {
+            Some(suffix)
+        }
+    }
+
+    pub fn value(&self) -> Option<f64> {
+        let (text, _) = self.split_into_parts();
+        text.parse::<f64>().ok()
+    }
+}
+
+#[derive(Debug, PartialEq, Eq, Copy, Clone)]
+pub enum Radix {
+    Binary = 2,
+    Octal = 8,
+    Decimal = 10,
+    Hexadecimal = 16,
+}
+
+impl Radix {
+    pub const ALL: &'static [Radix] =
+        &[Radix::Binary, Radix::Octal, Radix::Decimal, Radix::Hexadecimal];
+
+    const fn prefix_len(self) -> usize {
+        match self {
+            Self::Decimal => 0,
+            _ => 2,
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::ast::{self, make, FloatNumber, IntNumber};
+
+    fn check_float_suffix<'a>(lit: &str, expected: impl Into<Option<&'a str>>) {
+        assert_eq!(FloatNumber { syntax: make::tokens::literal(lit) }.suffix(), expected.into());
+    }
+
+    fn check_int_suffix<'a>(lit: &str, expected: impl Into<Option<&'a str>>) {
+        assert_eq!(IntNumber { syntax: make::tokens::literal(lit) }.suffix(), expected.into());
+    }
+
+    #[test]
+    fn test_float_number_suffix() {
+        check_float_suffix("123.0", None);
+        check_float_suffix("123f32", "f32");
+        check_float_suffix("123.0e", None);
+        check_float_suffix("123.0e4", None);
+        check_float_suffix("123.0ef32", "f32");
+        check_float_suffix("123.0E4f32", "f32");
+        check_float_suffix("1_2_3.0_f32", "f32");
+    }
+
+    #[test]
+    fn test_int_number_suffix() {
+        check_int_suffix("123", None);
+        check_int_suffix("123i32", "i32");
+        check_int_suffix("1_0_1_l_o_l", "l_o_l");
+        check_int_suffix("0b11", None);
+        check_int_suffix("0o11", None);
+        check_int_suffix("0xff", None);
+        check_int_suffix("0b11u32", "u32");
+        check_int_suffix("0o11u32", "u32");
+        check_int_suffix("0xffu32", "u32");
+    }
+
+    fn check_string_value<'a>(lit: &str, expected: impl Into<Option<&'a str>>) {
+        assert_eq!(
+            ast::String { syntax: make::tokens::literal(&format!("\"{}\"", lit)) }
+                .value()
+                .as_deref(),
+            expected.into()
+        );
+    }
+
+    #[test]
+    fn test_string_escape() {
+        check_string_value(r"foobar", "foobar");
+        check_string_value(r"\foobar", None);
+        check_string_value(r"\nfoobar", "\nfoobar");
+        check_string_value(r"C:\\Windows\\System32\\", "C:\\Windows\\System32\\");
+    }
+}
+
+impl ast::Char {
+    pub fn value(&self) -> Option<char> {
+        let mut text = self.text();
+        if text.starts_with('\'') {
+            text = &text[1..];
+        } else {
+            return None;
+        }
+        if text.ends_with('\'') {
+            text = &text[0..text.len() - 1];
+        }
+
+        unescape_char(text).ok()
+    }
+}
+
+impl ast::Byte {
+    pub fn value(&self) -> Option<u8> {
+        let mut text = self.text();
+        if text.starts_with("b\'") {
+            text = &text[2..];
+        } else {
+            return None;
+        }
+        if text.ends_with('\'') {
+            text = &text[0..text.len() - 1];
+        }
+
+        unescape_byte(text).ok()
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ast/traits.rs b/src/tools/rust-analyzer/crates/syntax/src/ast/traits.rs
new file mode 100644
index 000000000..aa2b7ed5c
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/ast/traits.rs
@@ -0,0 +1,136 @@
+//! Various traits that are implemented by ast nodes.
+//!
+//! The implementations are usually trivial, and live in generated.rs
+use itertools::Either;
+
+use crate::{
+    ast::{self, support, AstChildren, AstNode, AstToken},
+    syntax_node::SyntaxElementChildren,
+    SyntaxElement, SyntaxToken, T,
+};
+
+pub trait HasName: AstNode {
+    fn name(&self) -> Option<ast::Name> {
+        support::child(self.syntax())
+    }
+}
+
+pub trait HasVisibility: AstNode {
+    fn visibility(&self) -> Option<ast::Visibility> {
+        support::child(self.syntax())
+    }
+}
+
+pub trait HasLoopBody: AstNode {
+    fn loop_body(&self) -> Option<ast::BlockExpr> {
+        support::child(self.syntax())
+    }
+
+    fn label(&self) -> Option<ast::Label> {
+        support::child(self.syntax())
+    }
+}
+
+pub trait HasArgList: AstNode {
+    fn arg_list(&self) -> Option<ast::ArgList> {
+        support::child(self.syntax())
+    }
+}
+
+pub trait HasModuleItem: AstNode {
+    fn items(&self) -> AstChildren<ast::Item> {
+        support::children(self.syntax())
+    }
+}
+
+pub trait HasGenericParams: AstNode {
+    fn generic_param_list(&self) -> Option<ast::GenericParamList> {
+        support::child(self.syntax())
+    }
+
+    fn where_clause(&self) -> Option<ast::WhereClause> {
+        support::child(self.syntax())
+    }
+}
+
+pub trait HasTypeBounds: AstNode {
+    fn type_bound_list(&self) -> Option<ast::TypeBoundList> {
+        support::child(self.syntax())
+    }
+
+    fn colon_token(&self) -> Option<SyntaxToken> {
+        support::token(self.syntax(), T![:])
+    }
+}
+
+pub trait HasAttrs: AstNode {
+    fn attrs(&self) -> AstChildren<ast::Attr> {
+        support::children(self.syntax())
+    }
+    fn has_atom_attr(&self, atom: &str) -> bool {
+        self.attrs().filter_map(|x| x.as_simple_atom()).any(|x| x == atom)
+    }
+}
+
+pub trait HasDocComments: HasAttrs {
+    fn doc_comments(&self) -> DocCommentIter {
+        DocCommentIter { iter: self.syntax().children_with_tokens() }
+    }
+    fn doc_comments_and_attrs(&self) -> AttrDocCommentIter {
+        AttrDocCommentIter { iter: self.syntax().children_with_tokens() }
+    }
+}
+
+impl DocCommentIter {
+    pub fn from_syntax_node(syntax_node: &ast::SyntaxNode) -> DocCommentIter {
+        DocCommentIter { iter: syntax_node.children_with_tokens() }
+    }
+
+    #[cfg(test)]
+    pub fn doc_comment_text(self) -> Option<String> {
+        let docs = itertools::Itertools::join(
+            &mut self.filter_map(|comment| comment.doc_comment().map(ToOwned::to_owned)),
+            "\n",
+        );
+        if docs.is_empty() {
+            None
+        } else {
+            Some(docs)
+        }
+    }
+}
+
+pub struct DocCommentIter {
+    iter: SyntaxElementChildren,
+}
+
+impl Iterator for DocCommentIter {
+    type Item = ast::Comment;
+    fn next(&mut self) -> Option<ast::Comment> {
+        self.iter.by_ref().find_map(|el| {
+            el.into_token().and_then(ast::Comment::cast).filter(ast::Comment::is_doc)
+        })
+    }
+}
+
+pub struct AttrDocCommentIter {
+    iter: SyntaxElementChildren,
+}
+
+impl AttrDocCommentIter {
+    pub fn from_syntax_node(syntax_node: &ast::SyntaxNode) -> AttrDocCommentIter {
+        AttrDocCommentIter { iter: syntax_node.children_with_tokens() }
+    }
+}
+
+impl Iterator for AttrDocCommentIter {
+    type Item = Either<ast::Attr, ast::Comment>;
+    fn next(&mut self) -> Option<Self::Item> {
+        self.iter.by_ref().find_map(|el| match el {
+            SyntaxElement::Node(node) => ast::Attr::cast(node).map(Either::Left),
+            SyntaxElement::Token(tok) => {
+                ast::Comment::cast(tok).filter(ast::Comment::is_doc).map(Either::Right)
+            }
+        })
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/fuzz.rs b/src/tools/rust-analyzer/crates/syntax/src/fuzz.rs
new file mode 100644
index 000000000..256999fe0
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/fuzz.rs
@@ -0,0 +1,75 @@
+//! Some infrastructure for fuzzy testing.
+//!
+//! We don't normally run fuzzying, so this is hopelessly bitrotten :(
+
+use std::{
+    convert::TryInto,
+    str::{self, FromStr},
+};
+
+use text_edit::Indel;
+
+use crate::{validation, AstNode, SourceFile, TextRange};
+
+fn check_file_invariants(file: &SourceFile) {
+    let root = file.syntax();
+    validation::validate_block_structure(root);
+}
+
+pub fn check_parser(text: &str) {
+    let file = SourceFile::parse(text);
+    check_file_invariants(&file.tree());
+}
+
+#[derive(Debug, Clone)]
+pub struct CheckReparse {
+    text: String,
+    edit: Indel,
+    edited_text: String,
+}
+
+impl CheckReparse {
+    pub fn from_data(data: &[u8]) -> Option<Self> {
+        const PREFIX: &str = "fn main(){\n\t";
+        const SUFFIX: &str = "\n}";
+
+        let data = str::from_utf8(data).ok()?;
+        let mut lines = data.lines();
+        let delete_start = usize::from_str(lines.next()?).ok()? + PREFIX.len();
+        let delete_len = usize::from_str(lines.next()?).ok()?;
+        let insert = lines.next()?.to_string();
+        let text = lines.collect::<Vec<_>>().join("\n");
+        let text = format!("{}{}{}", PREFIX, text, SUFFIX);
+        text.get(delete_start..delete_start.checked_add(delete_len)?)?; // make sure delete is a valid range
+        let delete =
+            TextRange::at(delete_start.try_into().unwrap(), delete_len.try_into().unwrap());
+        let edited_text =
+            format!("{}{}{}", &text[..delete_start], &insert, &text[delete_start + delete_len..]);
+        let edit = Indel { insert, delete };
+        Some(CheckReparse { text, edit, edited_text })
+    }
+
+    pub fn run(&self) {
+        let parse = SourceFile::parse(&self.text);
+        let new_parse = parse.reparse(&self.edit);
+        check_file_invariants(&new_parse.tree());
+        assert_eq!(&new_parse.tree().syntax().text().to_string(), &self.edited_text);
+        let full_reparse = SourceFile::parse(&self.edited_text);
+        for (a, b) in
+            new_parse.tree().syntax().descendants().zip(full_reparse.tree().syntax().descendants())
+        {
+            if (a.kind(), a.text_range()) != (b.kind(), b.text_range()) {
+                eprint!("original:\n{:#?}", parse.tree().syntax());
+                eprint!("reparsed:\n{:#?}", new_parse.tree().syntax());
+                eprint!("full reparse:\n{:#?}", full_reparse.tree().syntax());
+                assert_eq!(
+                    format!("{:?}", a),
+                    format!("{:?}", b),
+                    "different syntax tree produced by the full reparse"
+                );
+            }
+        }
+        // FIXME
+        // assert_eq!(new_file.errors(), full_reparse.errors());
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/hacks.rs b/src/tools/rust-analyzer/crates/syntax/src/hacks.rs
new file mode 100644
index 000000000..a047f61fa
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/hacks.rs
@@ -0,0 +1,15 @@
+//! Things which exist to solve practial issues, but which shouldn't exist.
+//!
+//! Please avoid adding new usages of the functions in this module
+
+use crate::{ast, AstNode};
+
+pub fn parse_expr_from_str(s: &str) -> Option<ast::Expr> {
+    let s = s.trim();
+    let file = ast::SourceFile::parse(&format!("const _: () = {};", s));
+    let expr = file.syntax_node().descendants().find_map(ast::Expr::cast)?;
+    if expr.syntax().text() != s {
+        return None;
+    }
+    Some(expr)
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/lib.rs b/src/tools/rust-analyzer/crates/syntax/src/lib.rs
new file mode 100644
index 000000000..7fa354c0c
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/lib.rs
@@ -0,0 +1,358 @@
+//! Syntax Tree library used throughout the rust analyzer.
+//!
+//! Properties:
+//!   - easy and fast incremental re-parsing
+//!   - graceful handling of errors
+//!   - full-fidelity representation (*any* text can be precisely represented as
+//!     a syntax tree)
+//!
+//! For more information, see the [RFC]. Current implementation is inspired by
+//! the [Swift] one.
+//!
+//! The most interesting modules here are `syntax_node` (which defines concrete
+//! syntax tree) and `ast` (which defines abstract syntax tree on top of the
+//! CST). The actual parser live in a separate `parser` crate, though the
+//! lexer lives in this crate.
+//!
+//! See `api_walkthrough` test in this file for a quick API tour!
+//!
+//! [RFC]: <https://github.com/rust-lang/rfcs/pull/2256>
+//! [Swift]: <https://github.com/apple/swift/blob/13d593df6f359d0cb2fc81cfaac273297c539455/lib/Syntax/README.md>
+
+#![warn(rust_2018_idioms, unused_lifetimes, semicolon_in_expressions_from_macros)]
+
+#[allow(unused)]
+macro_rules! eprintln {
+    ($($tt:tt)*) => { stdx::eprintln!($($tt)*) };
+}
+
+mod syntax_node;
+mod syntax_error;
+mod parsing;
+mod validation;
+mod ptr;
+mod token_text;
+#[cfg(test)]
+mod tests;
+
+pub mod algo;
+pub mod ast;
+#[doc(hidden)]
+pub mod fuzz;
+pub mod utils;
+pub mod ted;
+pub mod hacks;
+
+use std::{marker::PhantomData, sync::Arc};
+
+use stdx::format_to;
+use text_edit::Indel;
+
+pub use crate::{
+    ast::{AstNode, AstToken},
+    ptr::{AstPtr, SyntaxNodePtr},
+    syntax_error::SyntaxError,
+    syntax_node::{
+        PreorderWithTokens, RustLanguage, SyntaxElement, SyntaxElementChildren, SyntaxNode,
+        SyntaxNodeChildren, SyntaxToken, SyntaxTreeBuilder,
+    },
+    token_text::TokenText,
+};
+pub use parser::{SyntaxKind, T};
+pub use rowan::{
+    api::Preorder, Direction, GreenNode, NodeOrToken, SyntaxText, TextRange, TextSize,
+    TokenAtOffset, WalkEvent,
+};
+pub use smol_str::SmolStr;
+
+/// `Parse` is the result of the parsing: a syntax tree and a collection of
+/// errors.
+///
+/// Note that we always produce a syntax tree, even for completely invalid
+/// files.
+#[derive(Debug, PartialEq, Eq)]
+pub struct Parse<T> {
+    green: GreenNode,
+    errors: Arc<Vec<SyntaxError>>,
+    _ty: PhantomData<fn() -> T>,
+}
+
+impl<T> Clone for Parse<T> {
+    fn clone(&self) -> Parse<T> {
+        Parse { green: self.green.clone(), errors: self.errors.clone(), _ty: PhantomData }
+    }
+}
+
+impl<T> Parse<T> {
+    fn new(green: GreenNode, errors: Vec<SyntaxError>) -> Parse<T> {
+        Parse { green, errors: Arc::new(errors), _ty: PhantomData }
+    }
+
+    pub fn syntax_node(&self) -> SyntaxNode {
+        SyntaxNode::new_root(self.green.clone())
+    }
+    pub fn errors(&self) -> &[SyntaxError] {
+        &*self.errors
+    }
+}
+
+impl<T: AstNode> Parse<T> {
+    pub fn to_syntax(self) -> Parse<SyntaxNode> {
+        Parse { green: self.green, errors: self.errors, _ty: PhantomData }
+    }
+
+    pub fn tree(&self) -> T {
+        T::cast(self.syntax_node()).unwrap()
+    }
+
+    pub fn ok(self) -> Result<T, Arc<Vec<SyntaxError>>> {
+        if self.errors.is_empty() {
+            Ok(self.tree())
+        } else {
+            Err(self.errors)
+        }
+    }
+}
+
+impl Parse<SyntaxNode> {
+    pub fn cast<N: AstNode>(self) -> Option<Parse<N>> {
+        if N::cast(self.syntax_node()).is_some() {
+            Some(Parse { green: self.green, errors: self.errors, _ty: PhantomData })
+        } else {
+            None
+        }
+    }
+}
+
+impl Parse<SourceFile> {
+    pub fn debug_dump(&self) -> String {
+        let mut buf = format!("{:#?}", self.tree().syntax());
+        for err in self.errors.iter() {
+            format_to!(buf, "error {:?}: {}\n", err.range(), err);
+        }
+        buf
+    }
+
+    pub fn reparse(&self, indel: &Indel) -> Parse<SourceFile> {
+        self.incremental_reparse(indel).unwrap_or_else(|| self.full_reparse(indel))
+    }
+
+    fn incremental_reparse(&self, indel: &Indel) -> Option<Parse<SourceFile>> {
+        // FIXME: validation errors are not handled here
+        parsing::incremental_reparse(self.tree().syntax(), indel, self.errors.to_vec()).map(
+            |(green_node, errors, _reparsed_range)| Parse {
+                green: green_node,
+                errors: Arc::new(errors),
+                _ty: PhantomData,
+            },
+        )
+    }
+
+    fn full_reparse(&self, indel: &Indel) -> Parse<SourceFile> {
+        let mut text = self.tree().syntax().text().to_string();
+        indel.apply(&mut text);
+        SourceFile::parse(&text)
+    }
+}
+
+/// `SourceFile` represents a parse tree for a single Rust file.
+pub use crate::ast::SourceFile;
+
+impl SourceFile {
+    pub fn parse(text: &str) -> Parse<SourceFile> {
+        let (green, mut errors) = parsing::parse_text(text);
+        let root = SyntaxNode::new_root(green.clone());
+
+        errors.extend(validation::validate(&root));
+
+        assert_eq!(root.kind(), SyntaxKind::SOURCE_FILE);
+        Parse { green, errors: Arc::new(errors), _ty: PhantomData }
+    }
+}
+
+/// Matches a `SyntaxNode` against an `ast` type.
+///
+/// # Example:
+///
+/// ```ignore
+/// match_ast! {
+///     match node {
+///         ast::CallExpr(it) => { ... },
+///         ast::MethodCallExpr(it) => { ... },
+///         ast::MacroCall(it) => { ... },
+///         _ => None,
+///     }
+/// }
+/// ```
+#[macro_export]
+macro_rules! match_ast {
+    (match $node:ident { $($tt:tt)* }) => { match_ast!(match ($node) { $($tt)* }) };
+
+    (match ($node:expr) {
+        $( $( $path:ident )::+ ($it:pat) => $res:expr, )*
+        _ => $catch_all:expr $(,)?
+    }) => {{
+        $( if let Some($it) = $($path::)+cast($node.clone()) { $res } else )*
+        { $catch_all }
+    }};
+}
+
+/// This test does not assert anything and instead just shows off the crate's
+/// API.
+#[test]
+fn api_walkthrough() {
+    use ast::{HasModuleItem, HasName};
+
+    let source_code = "
+        fn foo() {
+            1 + 1
+        }
+    ";
+    // `SourceFile` is the main entry point.
+    //
+    // The `parse` method returns a `Parse` -- a pair of syntax tree and a list
+    // of errors. That is, syntax tree is constructed even in presence of errors.
+    let parse = SourceFile::parse(source_code);
+    assert!(parse.errors().is_empty());
+
+    // The `tree` method returns an owned syntax node of type `SourceFile`.
+    // Owned nodes are cheap: inside, they are `Rc` handles to the underling data.
+    let file: SourceFile = parse.tree();
+
+    // `SourceFile` is the root of the syntax tree. We can iterate file's items.
+    // Let's fetch the `foo` function.
+    let mut func = None;
+    for item in file.items() {
+        match item {
+            ast::Item::Fn(f) => func = Some(f),
+            _ => unreachable!(),
+        }
+    }
+    let func: ast::Fn = func.unwrap();
+
+    // Each AST node has a bunch of getters for children. All getters return
+    // `Option`s though, to account for incomplete code. Some getters are common
+    // for several kinds of node. In this case, a trait like `ast::NameOwner`
+    // usually exists. By convention, all ast types should be used with `ast::`
+    // qualifier.
+    let name: Option<ast::Name> = func.name();
+    let name = name.unwrap();
+    assert_eq!(name.text(), "foo");
+
+    // Let's get the `1 + 1` expression!
+    let body: ast::BlockExpr = func.body().unwrap();
+    let stmt_list: ast::StmtList = body.stmt_list().unwrap();
+    let expr: ast::Expr = stmt_list.tail_expr().unwrap();
+
+    // Enums are used to group related ast nodes together, and can be used for
+    // matching. However, because there are no public fields, it's possible to
+    // match only the top level enum: that is the price we pay for increased API
+    // flexibility
+    let bin_expr: &ast::BinExpr = match &expr {
+        ast::Expr::BinExpr(e) => e,
+        _ => unreachable!(),
+    };
+
+    // Besides the "typed" AST API, there's an untyped CST one as well.
+    // To switch from AST to CST, call `.syntax()` method:
+    let expr_syntax: &SyntaxNode = expr.syntax();
+
+    // Note how `expr` and `bin_expr` are in fact the same node underneath:
+    assert!(expr_syntax == bin_expr.syntax());
+
+    // To go from CST to AST, `AstNode::cast` function is used:
+    let _expr: ast::Expr = match ast::Expr::cast(expr_syntax.clone()) {
+        Some(e) => e,
+        None => unreachable!(),
+    };
+
+    // The two properties each syntax node has is a `SyntaxKind`:
+    assert_eq!(expr_syntax.kind(), SyntaxKind::BIN_EXPR);
+
+    // And text range:
+    assert_eq!(expr_syntax.text_range(), TextRange::new(32.into(), 37.into()));
+
+    // You can get node's text as a `SyntaxText` object, which will traverse the
+    // tree collecting token's text:
+    let text: SyntaxText = expr_syntax.text();
+    assert_eq!(text.to_string(), "1 + 1");
+
+    // There's a bunch of traversal methods on `SyntaxNode`:
+    assert_eq!(expr_syntax.parent().as_ref(), Some(stmt_list.syntax()));
+    assert_eq!(stmt_list.syntax().first_child_or_token().map(|it| it.kind()), Some(T!['{']));
+    assert_eq!(
+        expr_syntax.next_sibling_or_token().map(|it| it.kind()),
+        Some(SyntaxKind::WHITESPACE)
+    );
+
+    // As well as some iterator helpers:
+    let f = expr_syntax.ancestors().find_map(ast::Fn::cast);
+    assert_eq!(f, Some(func));
+    assert!(expr_syntax.siblings_with_tokens(Direction::Next).any(|it| it.kind() == T!['}']));
+    assert_eq!(
+        expr_syntax.descendants_with_tokens().count(),
+        8, // 5 tokens `1`, ` `, `+`, ` `, `!`
+           // 2 child literal expressions: `1`, `1`
+           // 1 the node itself: `1 + 1`
+    );
+
+    // There's also a `preorder` method with a more fine-grained iteration control:
+    let mut buf = String::new();
+    let mut indent = 0;
+    for event in expr_syntax.preorder_with_tokens() {
+        match event {
+            WalkEvent::Enter(node) => {
+                let text = match &node {
+                    NodeOrToken::Node(it) => it.text().to_string(),
+                    NodeOrToken::Token(it) => it.text().to_string(),
+                };
+                format_to!(buf, "{:indent$}{:?} {:?}\n", " ", text, node.kind(), indent = indent);
+                indent += 2;
+            }
+            WalkEvent::Leave(_) => indent -= 2,
+        }
+    }
+    assert_eq!(indent, 0);
+    assert_eq!(
+        buf.trim(),
+        r#"
+"1 + 1" BIN_EXPR
+  "1" LITERAL
+    "1" INT_NUMBER
+  " " WHITESPACE
+  "+" PLUS
+  " " WHITESPACE
+  "1" LITERAL
+    "1" INT_NUMBER
+"#
+        .trim()
+    );
+
+    // To recursively process the tree, there are three approaches:
+    // 1. explicitly call getter methods on AST nodes.
+    // 2. use descendants and `AstNode::cast`.
+    // 3. use descendants and `match_ast!`.
+    //
+    // Here's how the first one looks like:
+    let exprs_cast: Vec<String> = file
+        .syntax()
+        .descendants()
+        .filter_map(ast::Expr::cast)
+        .map(|expr| expr.syntax().text().to_string())
+        .collect();
+
+    // An alternative is to use a macro.
+    let mut exprs_visit = Vec::new();
+    for node in file.syntax().descendants() {
+        match_ast! {
+            match node {
+                ast::Expr(it) => {
+                    let res = it.syntax().text().to_string();
+                    exprs_visit.push(res);
+                },
+                _ => (),
+            }
+        }
+    }
+    assert_eq!(exprs_cast, exprs_visit);
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/parsing.rs b/src/tools/rust-analyzer/crates/syntax/src/parsing.rs
new file mode 100644
index 000000000..047e670c9
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/parsing.rs
@@ -0,0 +1,46 @@
+//! Lexing, bridging to parser (which does the actual parsing) and
+//! incremental reparsing.
+
+mod reparsing;
+
+use rowan::TextRange;
+
+use crate::{syntax_node::GreenNode, SyntaxError, SyntaxTreeBuilder};
+
+pub(crate) use crate::parsing::reparsing::incremental_reparse;
+
+pub(crate) fn parse_text(text: &str) -> (GreenNode, Vec<SyntaxError>) {
+    let lexed = parser::LexedStr::new(text);
+    let parser_input = lexed.to_input();
+    let parser_output = parser::TopEntryPoint::SourceFile.parse(&parser_input);
+    let (node, errors, _eof) = build_tree(lexed, parser_output);
+    (node, errors)
+}
+
+pub(crate) fn build_tree(
+    lexed: parser::LexedStr<'_>,
+    parser_output: parser::Output,
+) -> (GreenNode, Vec<SyntaxError>, bool) {
+    let mut builder = SyntaxTreeBuilder::default();
+
+    let is_eof = lexed.intersperse_trivia(&parser_output, &mut |step| match step {
+        parser::StrStep::Token { kind, text } => builder.token(kind, text),
+        parser::StrStep::Enter { kind } => builder.start_node(kind),
+        parser::StrStep::Exit => builder.finish_node(),
+        parser::StrStep::Error { msg, pos } => {
+            builder.error(msg.to_string(), pos.try_into().unwrap())
+        }
+    });
+
+    let (node, mut errors) = builder.finish_raw();
+    for (i, err) in lexed.errors() {
+        let text_range = lexed.text_range(i);
+        let text_range = TextRange::new(
+            text_range.start.try_into().unwrap(),
+            text_range.end.try_into().unwrap(),
+        );
+        errors.push(SyntaxError::new(err, text_range))
+    }
+
+    (node, errors, is_eof)
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/parsing/reparsing.rs b/src/tools/rust-analyzer/crates/syntax/src/parsing/reparsing.rs
new file mode 100644
index 000000000..701e6232d
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/parsing/reparsing.rs
@@ -0,0 +1,441 @@
+//! Implementation of incremental re-parsing.
+//!
+//! We use two simple strategies for this:
+//!   - if the edit modifies only a single token (like changing an identifier's
+//!     letter), we replace only this token.
+//!   - otherwise, we search for the nearest `{}` block which contains the edit
+//!     and try to parse only this block.
+
+use parser::Reparser;
+use text_edit::Indel;
+
+use crate::{
+    parsing::build_tree,
+    syntax_node::{GreenNode, GreenToken, NodeOrToken, SyntaxElement, SyntaxNode},
+    SyntaxError,
+    SyntaxKind::*,
+    TextRange, TextSize, T,
+};
+
+pub(crate) fn incremental_reparse(
+    node: &SyntaxNode,
+    edit: &Indel,
+    errors: Vec<SyntaxError>,
+) -> Option<(GreenNode, Vec<SyntaxError>, TextRange)> {
+    if let Some((green, new_errors, old_range)) = reparse_token(node, edit) {
+        return Some((green, merge_errors(errors, new_errors, old_range, edit), old_range));
+    }
+
+    if let Some((green, new_errors, old_range)) = reparse_block(node, edit) {
+        return Some((green, merge_errors(errors, new_errors, old_range, edit), old_range));
+    }
+    None
+}
+
+fn reparse_token(
+    root: &SyntaxNode,
+    edit: &Indel,
+) -> Option<(GreenNode, Vec<SyntaxError>, TextRange)> {
+    let prev_token = root.covering_element(edit.delete).as_token()?.clone();
+    let prev_token_kind = prev_token.kind();
+    match prev_token_kind {
+        WHITESPACE | COMMENT | IDENT | STRING => {
+            if prev_token_kind == WHITESPACE || prev_token_kind == COMMENT {
+                // removing a new line may extends previous token
+                let deleted_range = edit.delete - prev_token.text_range().start();
+                if prev_token.text()[deleted_range].contains('\n') {
+                    return None;
+                }
+            }
+
+            let mut new_text = get_text_after_edit(prev_token.clone().into(), edit);
+            let (new_token_kind, new_err) = parser::LexedStr::single_token(&new_text)?;
+
+            if new_token_kind != prev_token_kind
+                || (new_token_kind == IDENT && is_contextual_kw(&new_text))
+            {
+                return None;
+            }
+
+            // Check that edited token is not a part of the bigger token.
+            // E.g. if for source code `bruh"str"` the user removed `ruh`, then
+            // `b` no longer remains an identifier, but becomes a part of byte string literal
+            if let Some(next_char) = root.text().char_at(prev_token.text_range().end()) {
+                new_text.push(next_char);
+                let token_with_next_char = parser::LexedStr::single_token(&new_text);
+                if let Some((_kind, _error)) = token_with_next_char {
+                    return None;
+                }
+                new_text.pop();
+            }
+
+            let new_token = GreenToken::new(rowan::SyntaxKind(prev_token_kind.into()), &new_text);
+            let range = TextRange::up_to(TextSize::of(&new_text));
+            Some((
+                prev_token.replace_with(new_token),
+                new_err.into_iter().map(|msg| SyntaxError::new(msg, range)).collect(),
+                prev_token.text_range(),
+            ))
+        }
+        _ => None,
+    }
+}
+
+fn reparse_block(
+    root: &SyntaxNode,
+    edit: &Indel,
+) -> Option<(GreenNode, Vec<SyntaxError>, TextRange)> {
+    let (node, reparser) = find_reparsable_node(root, edit.delete)?;
+    let text = get_text_after_edit(node.clone().into(), edit);
+
+    let lexed = parser::LexedStr::new(text.as_str());
+    let parser_input = lexed.to_input();
+    if !is_balanced(&lexed) {
+        return None;
+    }
+
+    let tree_traversal = reparser.parse(&parser_input);
+
+    let (green, new_parser_errors, _eof) = build_tree(lexed, tree_traversal);
+
+    Some((node.replace_with(green), new_parser_errors, node.text_range()))
+}
+
+fn get_text_after_edit(element: SyntaxElement, edit: &Indel) -> String {
+    let edit = Indel::replace(edit.delete - element.text_range().start(), edit.insert.clone());
+
+    let mut text = match element {
+        NodeOrToken::Token(token) => token.text().to_string(),
+        NodeOrToken::Node(node) => node.text().to_string(),
+    };
+    edit.apply(&mut text);
+    text
+}
+
+fn is_contextual_kw(text: &str) -> bool {
+    matches!(text, "auto" | "default" | "union")
+}
+
+fn find_reparsable_node(node: &SyntaxNode, range: TextRange) -> Option<(SyntaxNode, Reparser)> {
+    let node = node.covering_element(range);
+
+    node.ancestors().find_map(|node| {
+        let first_child = node.first_child_or_token().map(|it| it.kind());
+        let parent = node.parent().map(|it| it.kind());
+        Reparser::for_node(node.kind(), first_child, parent).map(|r| (node, r))
+    })
+}
+
+fn is_balanced(lexed: &parser::LexedStr<'_>) -> bool {
+    if lexed.is_empty() || lexed.kind(0) != T!['{'] || lexed.kind(lexed.len() - 1) != T!['}'] {
+        return false;
+    }
+    let mut balance = 0usize;
+    for i in 1..lexed.len() - 1 {
+        match lexed.kind(i) {
+            T!['{'] => balance += 1,
+            T!['}'] => {
+                balance = match balance.checked_sub(1) {
+                    Some(b) => b,
+                    None => return false,
+                }
+            }
+            _ => (),
+        }
+    }
+    balance == 0
+}
+
+fn merge_errors(
+    old_errors: Vec<SyntaxError>,
+    new_errors: Vec<SyntaxError>,
+    range_before_reparse: TextRange,
+    edit: &Indel,
+) -> Vec<SyntaxError> {
+    let mut res = Vec::new();
+
+    for old_err in old_errors {
+        let old_err_range = old_err.range();
+        if old_err_range.end() <= range_before_reparse.start() {
+            res.push(old_err);
+        } else if old_err_range.start() >= range_before_reparse.end() {
+            let inserted_len = TextSize::of(&edit.insert);
+            res.push(old_err.with_range((old_err_range + inserted_len) - edit.delete.len()));
+            // Note: extra parens are intentional to prevent uint underflow, HWAB (here was a bug)
+        }
+    }
+    res.extend(new_errors.into_iter().map(|new_err| {
+        // fighting borrow checker with a variable ;)
+        let offseted_range = new_err.range() + range_before_reparse.start();
+        new_err.with_range(offseted_range)
+    }));
+    res
+}
+
+#[cfg(test)]
+mod tests {
+    use test_utils::{assert_eq_text, extract_range};
+
+    use super::*;
+    use crate::{AstNode, Parse, SourceFile};
+
+    fn do_check(before: &str, replace_with: &str, reparsed_len: u32) {
+        let (range, before) = extract_range(before);
+        let edit = Indel::replace(range, replace_with.to_owned());
+        let after = {
+            let mut after = before.clone();
+            edit.apply(&mut after);
+            after
+        };
+
+        let fully_reparsed = SourceFile::parse(&after);
+        let incrementally_reparsed: Parse<SourceFile> = {
+            let before = SourceFile::parse(&before);
+            let (green, new_errors, range) =
+                incremental_reparse(before.tree().syntax(), &edit, before.errors.to_vec()).unwrap();
+            assert_eq!(range.len(), reparsed_len.into(), "reparsed fragment has wrong length");
+            Parse::new(green, new_errors)
+        };
+
+        assert_eq_text!(
+            &format!("{:#?}", fully_reparsed.tree().syntax()),
+            &format!("{:#?}", incrementally_reparsed.tree().syntax()),
+        );
+        assert_eq!(fully_reparsed.errors(), incrementally_reparsed.errors());
+    }
+
+    #[test] // FIXME: some test here actually test token reparsing
+    fn reparse_block_tests() {
+        do_check(
+            r"
+fn foo() {
+    let x = foo + $0bar$0
+}
+",
+            "baz",
+            3,
+        );
+        do_check(
+            r"
+fn foo() {
+    let x = foo$0 + bar$0
+}
+",
+            "baz",
+            25,
+        );
+        do_check(
+            r"
+struct Foo {
+    f: foo$0$0
+}
+",
+            ",\n    g: (),",
+            14,
+        );
+        do_check(
+            r"
+fn foo {
+    let;
+    1 + 1;
+    $092$0;
+}
+",
+            "62",
+            31, // FIXME: reparse only int literal here
+        );
+        do_check(
+            r"
+mod foo {
+    fn $0$0
+}
+",
+            "bar",
+            11,
+        );
+
+        do_check(
+            r"
+trait Foo {
+    type $0Foo$0;
+}
+",
+            "Output",
+            3,
+        );
+        do_check(
+            r"
+impl IntoIterator<Item=i32> for Foo {
+    f$0$0
+}
+",
+            "n next(",
+            9,
+        );
+        do_check(r"use a::b::{foo,$0,bar$0};", "baz", 10);
+        do_check(
+            r"
+pub enum A {
+    Foo$0$0
+}
+",
+            "\nBar;\n",
+            11,
+        );
+        do_check(
+            r"
+foo!{a, b$0$0 d}
+",
+            ", c[3]",
+            8,
+        );
+        do_check(
+            r"
+fn foo() {
+    vec![$0$0]
+}
+",
+            "123",
+            14,
+        );
+        do_check(
+            r"
+extern {
+    fn$0;$0
+}
+",
+            " exit(code: c_int)",
+            11,
+        );
+    }
+
+    #[test]
+    fn reparse_token_tests() {
+        do_check(
+            r"$0$0
+fn foo() -> i32 { 1 }
+",
+            "\n\n\n   \n",
+            1,
+        );
+        do_check(
+            r"
+fn foo() -> $0$0 {}
+",
+            "  \n",
+            2,
+        );
+        do_check(
+            r"
+fn $0foo$0() -> i32 { 1 }
+",
+            "bar",
+            3,
+        );
+        do_check(
+            r"
+fn foo$0$0foo() {  }
+",
+            "bar",
+            6,
+        );
+        do_check(
+            r"
+fn foo /* $0$0 */ () {}
+",
+            "some comment",
+            6,
+        );
+        do_check(
+            r"
+fn baz $0$0 () {}
+",
+            "    \t\t\n\n",
+            2,
+        );
+        do_check(
+            r"
+fn baz $0$0 () {}
+",
+            "    \t\t\n\n",
+            2,
+        );
+        do_check(
+            r"
+/// foo $0$0omment
+mod { }
+",
+            "c",
+            14,
+        );
+        do_check(
+            r#"
+fn -> &str { "Hello$0$0" }
+"#,
+            ", world",
+            7,
+        );
+        do_check(
+            r#"
+fn -> &str { // "Hello$0$0"
+"#,
+            ", world",
+            10,
+        );
+        do_check(
+            r##"
+fn -> &str { r#"Hello$0$0"#
+"##,
+            ", world",
+            10,
+        );
+        do_check(
+            r"
+#[derive($0Copy$0)]
+enum Foo {
+
+}
+",
+            "Clone",
+            4,
+        );
+    }
+
+    #[test]
+    fn reparse_str_token_with_error_unchanged() {
+        do_check(r#""$0Unclosed$0 string literal"#, "Still unclosed", 24);
+    }
+
+    #[test]
+    fn reparse_str_token_with_error_fixed() {
+        do_check(r#""unterinated$0$0"#, "\"", 12);
+    }
+
+    #[test]
+    fn reparse_block_with_error_in_middle_unchanged() {
+        do_check(
+            r#"fn main() {
+                if {}
+                32 + 4$0$0
+                return
+                if {}
+            }"#,
+            "23",
+            105,
+        )
+    }
+
+    #[test]
+    fn reparse_block_with_error_in_middle_fixed() {
+        do_check(
+            r#"fn main() {
+                if {}
+                32 + 4$0$0
+                return
+                if {}
+            }"#,
+            ";",
+            105,
+        )
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ptr.rs b/src/tools/rust-analyzer/crates/syntax/src/ptr.rs
new file mode 100644
index 000000000..a886972ff
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/ptr.rs
@@ -0,0 +1,104 @@
+//! In rust-analyzer, syntax trees are transient objects.
+//!
+//! That means that we create trees when we need them, and tear them down to
+//! save memory. In this architecture, hanging on to a particular syntax node
+//! for a long time is ill-advisable, as that keeps the whole tree resident.
+//!
+//! Instead, we provide a [`SyntaxNodePtr`] type, which stores information about
+//! *location* of a particular syntax node in a tree. Its a small type which can
+//! be cheaply stored, and which can be resolved to a real [`SyntaxNode`] when
+//! necessary.
+
+use std::{
+    hash::{Hash, Hasher},
+    marker::PhantomData,
+};
+
+use rowan::TextRange;
+
+use crate::{syntax_node::RustLanguage, AstNode, SyntaxNode};
+
+/// A "pointer" to a [`SyntaxNode`], via location in the source code.
+pub type SyntaxNodePtr = rowan::ast::SyntaxNodePtr<RustLanguage>;
+
+/// Like `SyntaxNodePtr`, but remembers the type of node.
+#[derive(Debug)]
+pub struct AstPtr<N: AstNode> {
+    raw: SyntaxNodePtr,
+    _ty: PhantomData<fn() -> N>,
+}
+
+impl<N: AstNode> Clone for AstPtr<N> {
+    fn clone(&self) -> AstPtr<N> {
+        AstPtr { raw: self.raw.clone(), _ty: PhantomData }
+    }
+}
+
+impl<N: AstNode> Eq for AstPtr<N> {}
+
+impl<N: AstNode> PartialEq for AstPtr<N> {
+    fn eq(&self, other: &AstPtr<N>) -> bool {
+        self.raw == other.raw
+    }
+}
+
+impl<N: AstNode> Hash for AstPtr<N> {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.raw.hash(state);
+    }
+}
+
+impl<N: AstNode> AstPtr<N> {
+    pub fn new(node: &N) -> AstPtr<N> {
+        AstPtr { raw: SyntaxNodePtr::new(node.syntax()), _ty: PhantomData }
+    }
+
+    pub fn to_node(&self, root: &SyntaxNode) -> N {
+        let syntax_node = self.raw.to_node(root);
+        N::cast(syntax_node).unwrap()
+    }
+
+    pub fn syntax_node_ptr(&self) -> SyntaxNodePtr {
+        self.raw.clone()
+    }
+
+    pub fn text_range(&self) -> TextRange {
+        self.raw.text_range()
+    }
+
+    pub fn cast<U: AstNode>(self) -> Option<AstPtr<U>> {
+        if !U::can_cast(self.raw.kind()) {
+            return None;
+        }
+        Some(AstPtr { raw: self.raw, _ty: PhantomData })
+    }
+
+    pub fn upcast<M: AstNode>(self) -> AstPtr<M>
+    where
+        N: Into<M>,
+    {
+        AstPtr { raw: self.raw, _ty: PhantomData }
+    }
+
+    /// Like `SyntaxNodePtr::cast` but the trait bounds work out.
+    pub fn try_from_raw(raw: SyntaxNodePtr) -> Option<AstPtr<N>> {
+        N::can_cast(raw.kind()).then(|| AstPtr { raw, _ty: PhantomData })
+    }
+}
+
+impl<N: AstNode> From<AstPtr<N>> for SyntaxNodePtr {
+    fn from(ptr: AstPtr<N>) -> SyntaxNodePtr {
+        ptr.raw
+    }
+}
+
+#[test]
+fn test_local_syntax_ptr() {
+    use crate::{ast, AstNode, SourceFile};
+
+    let file = SourceFile::parse("struct Foo { f: u32, }").ok().unwrap();
+    let field = file.syntax().descendants().find_map(ast::RecordField::cast).unwrap();
+    let ptr = SyntaxNodePtr::new(field.syntax());
+    let field_syntax = ptr.to_node(file.syntax());
+    assert_eq!(field.syntax(), &field_syntax);
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/syntax_error.rs b/src/tools/rust-analyzer/crates/syntax/src/syntax_error.rs
new file mode 100644
index 000000000..dc6130bd6
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/syntax_error.rs
@@ -0,0 +1,44 @@
+//! See docs for `SyntaxError`.
+
+use std::fmt;
+
+use crate::{TextRange, TextSize};
+
+/// Represents the result of unsuccessful tokenization, parsing
+/// or tree validation.
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct SyntaxError(String, TextRange);
+
+// FIXME: there was an unused SyntaxErrorKind previously (before this enum was removed)
+// It was introduced in this PR: https://github.com/rust-lang/rust-analyzer/pull/846/files#diff-827da9b03b8f9faa1bade5cdd44d5dafR95
+// but it was not removed by a mistake.
+//
+// So, we need to find a place where to stick validation for attributes in match clauses.
+// Code before refactor:
+// InvalidMatchInnerAttr => {
+//    write!(f, "Inner attributes are only allowed directly after the opening brace of the match expression")
+// }
+
+impl SyntaxError {
+    pub fn new(message: impl Into<String>, range: TextRange) -> Self {
+        Self(message.into(), range)
+    }
+    pub fn new_at_offset(message: impl Into<String>, offset: TextSize) -> Self {
+        Self(message.into(), TextRange::empty(offset))
+    }
+
+    pub fn range(&self) -> TextRange {
+        self.1
+    }
+
+    pub fn with_range(mut self, range: TextRange) -> Self {
+        self.1 = range;
+        self
+    }
+}
+
+impl fmt::Display for SyntaxError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/syntax_node.rs b/src/tools/rust-analyzer/crates/syntax/src/syntax_node.rs
new file mode 100644
index 000000000..a08c01597
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/syntax_node.rs
@@ -0,0 +1,75 @@
+//! This module defines Concrete Syntax Tree (CST), used by rust-analyzer.
+//!
+//! The CST includes comments and whitespace, provides a single node type,
+//! `SyntaxNode`, and a basic traversal API (parent, children, siblings).
+//!
+//! The *real* implementation is in the (language-agnostic) `rowan` crate, this
+//! module just wraps its API.
+
+use rowan::{GreenNodeBuilder, Language};
+
+use crate::{Parse, SyntaxError, SyntaxKind, TextSize};
+
+pub(crate) use rowan::{GreenNode, GreenToken, NodeOrToken};
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub enum RustLanguage {}
+impl Language for RustLanguage {
+    type Kind = SyntaxKind;
+
+    fn kind_from_raw(raw: rowan::SyntaxKind) -> SyntaxKind {
+        SyntaxKind::from(raw.0)
+    }
+
+    fn kind_to_raw(kind: SyntaxKind) -> rowan::SyntaxKind {
+        rowan::SyntaxKind(kind.into())
+    }
+}
+
+pub type SyntaxNode = rowan::SyntaxNode<RustLanguage>;
+pub type SyntaxToken = rowan::SyntaxToken<RustLanguage>;
+pub type SyntaxElement = rowan::SyntaxElement<RustLanguage>;
+pub type SyntaxNodeChildren = rowan::SyntaxNodeChildren<RustLanguage>;
+pub type SyntaxElementChildren = rowan::SyntaxElementChildren<RustLanguage>;
+pub type PreorderWithTokens = rowan::api::PreorderWithTokens<RustLanguage>;
+
+#[derive(Default)]
+pub struct SyntaxTreeBuilder {
+    errors: Vec<SyntaxError>,
+    inner: GreenNodeBuilder<'static>,
+}
+
+impl SyntaxTreeBuilder {
+    pub(crate) fn finish_raw(self) -> (GreenNode, Vec<SyntaxError>) {
+        let green = self.inner.finish();
+        (green, self.errors)
+    }
+
+    pub fn finish(self) -> Parse<SyntaxNode> {
+        let (green, errors) = self.finish_raw();
+        // Disable block validation, see https://github.com/rust-lang/rust-analyzer/pull/10357
+        if cfg!(debug_assertions) && false {
+            let node = SyntaxNode::new_root(green.clone());
+            crate::validation::validate_block_structure(&node);
+        }
+        Parse::new(green, errors)
+    }
+
+    pub fn token(&mut self, kind: SyntaxKind, text: &str) {
+        let kind = RustLanguage::kind_to_raw(kind);
+        self.inner.token(kind, text);
+    }
+
+    pub fn start_node(&mut self, kind: SyntaxKind) {
+        let kind = RustLanguage::kind_to_raw(kind);
+        self.inner.start_node(kind);
+    }
+
+    pub fn finish_node(&mut self) {
+        self.inner.finish_node();
+    }
+
+    pub fn error(&mut self, error: String, text_pos: TextSize) {
+        self.errors.push(SyntaxError::new_at_offset(error, text_pos));
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ted.rs b/src/tools/rust-analyzer/crates/syntax/src/ted.rs
new file mode 100644
index 000000000..a47b4b11c
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/ted.rs
@@ -0,0 +1,206 @@
+//! Primitive tree editor, ed for trees.
+//!
+//! The `_raw`-suffixed functions insert elements as is, unsuffixed versions fix
+//! up elements around the edges.
+use std::{mem, ops::RangeInclusive};
+
+use parser::T;
+
+use crate::{
+    ast::{self, edit::IndentLevel, make, AstNode},
+    SyntaxElement, SyntaxKind, SyntaxNode, SyntaxToken,
+};
+
+/// Utility trait to allow calling `ted` functions with references or owned
+/// nodes. Do not use outside of this module.
+pub trait Element {
+    fn syntax_element(self) -> SyntaxElement;
+}
+
+impl<E: Element + Clone> Element for &'_ E {
+    fn syntax_element(self) -> SyntaxElement {
+        self.clone().syntax_element()
+    }
+}
+impl Element for SyntaxElement {
+    fn syntax_element(self) -> SyntaxElement {
+        self
+    }
+}
+impl Element for SyntaxNode {
+    fn syntax_element(self) -> SyntaxElement {
+        self.into()
+    }
+}
+impl Element for SyntaxToken {
+    fn syntax_element(self) -> SyntaxElement {
+        self.into()
+    }
+}
+
+#[derive(Debug)]
+pub struct Position {
+    repr: PositionRepr,
+}
+
+#[derive(Debug)]
+enum PositionRepr {
+    FirstChild(SyntaxNode),
+    After(SyntaxElement),
+}
+
+impl Position {
+    pub fn after(elem: impl Element) -> Position {
+        let repr = PositionRepr::After(elem.syntax_element());
+        Position { repr }
+    }
+    pub fn before(elem: impl Element) -> Position {
+        let elem = elem.syntax_element();
+        let repr = match elem.prev_sibling_or_token() {
+            Some(it) => PositionRepr::After(it),
+            None => PositionRepr::FirstChild(elem.parent().unwrap()),
+        };
+        Position { repr }
+    }
+    pub fn first_child_of(node: &(impl Into<SyntaxNode> + Clone)) -> Position {
+        let repr = PositionRepr::FirstChild(node.clone().into());
+        Position { repr }
+    }
+    pub fn last_child_of(node: &(impl Into<SyntaxNode> + Clone)) -> Position {
+        let node = node.clone().into();
+        let repr = match node.last_child_or_token() {
+            Some(it) => PositionRepr::After(it),
+            None => PositionRepr::FirstChild(node),
+        };
+        Position { repr }
+    }
+}
+
+pub fn insert(position: Position, elem: impl Element) {
+    insert_all(position, vec![elem.syntax_element()]);
+}
+pub fn insert_raw(position: Position, elem: impl Element) {
+    insert_all_raw(position, vec![elem.syntax_element()]);
+}
+pub fn insert_all(position: Position, mut elements: Vec<SyntaxElement>) {
+    if let Some(first) = elements.first() {
+        if let Some(ws) = ws_before(&position, first) {
+            elements.insert(0, ws.into());
+        }
+    }
+    if let Some(last) = elements.last() {
+        if let Some(ws) = ws_after(&position, last) {
+            elements.push(ws.into());
+        }
+    }
+    insert_all_raw(position, elements);
+}
+pub fn insert_all_raw(position: Position, elements: Vec<SyntaxElement>) {
+    let (parent, index) = match position.repr {
+        PositionRepr::FirstChild(parent) => (parent, 0),
+        PositionRepr::After(child) => (child.parent().unwrap(), child.index() + 1),
+    };
+    parent.splice_children(index..index, elements);
+}
+
+pub fn remove(elem: impl Element) {
+    elem.syntax_element().detach();
+}
+pub fn remove_all(range: RangeInclusive<SyntaxElement>) {
+    replace_all(range, Vec::new());
+}
+pub fn remove_all_iter(range: impl IntoIterator<Item = SyntaxElement>) {
+    let mut it = range.into_iter();
+    if let Some(mut first) = it.next() {
+        match it.last() {
+            Some(mut last) => {
+                if first.index() > last.index() {
+                    mem::swap(&mut first, &mut last);
+                }
+                remove_all(first..=last);
+            }
+            None => remove(first),
+        }
+    }
+}
+
+pub fn replace(old: impl Element, new: impl Element) {
+    replace_with_many(old, vec![new.syntax_element()]);
+}
+pub fn replace_with_many(old: impl Element, new: Vec<SyntaxElement>) {
+    let old = old.syntax_element();
+    replace_all(old.clone()..=old, new);
+}
+pub fn replace_all(range: RangeInclusive<SyntaxElement>, new: Vec<SyntaxElement>) {
+    let start = range.start().index();
+    let end = range.end().index();
+    let parent = range.start().parent().unwrap();
+    parent.splice_children(start..end + 1, new);
+}
+
+pub fn append_child(node: &(impl Into<SyntaxNode> + Clone), child: impl Element) {
+    let position = Position::last_child_of(node);
+    insert(position, child);
+}
+pub fn append_child_raw(node: &(impl Into<SyntaxNode> + Clone), child: impl Element) {
+    let position = Position::last_child_of(node);
+    insert_raw(position, child);
+}
+
+fn ws_before(position: &Position, new: &SyntaxElement) -> Option<SyntaxToken> {
+    let prev = match &position.repr {
+        PositionRepr::FirstChild(_) => return None,
+        PositionRepr::After(it) => it,
+    };
+
+    if prev.kind() == T!['{'] && new.kind() == SyntaxKind::USE {
+        if let Some(item_list) = prev.parent().and_then(ast::ItemList::cast) {
+            let mut indent = IndentLevel::from_element(&item_list.syntax().clone().into());
+            indent.0 += 1;
+            return Some(make::tokens::whitespace(&format!("\n{}", indent)));
+        }
+    }
+
+    if prev.kind() == T!['{'] && ast::Stmt::can_cast(new.kind()) {
+        if let Some(stmt_list) = prev.parent().and_then(ast::StmtList::cast) {
+            let mut indent = IndentLevel::from_element(&stmt_list.syntax().clone().into());
+            indent.0 += 1;
+            return Some(make::tokens::whitespace(&format!("\n{}", indent)));
+        }
+    }
+
+    ws_between(prev, new)
+}
+fn ws_after(position: &Position, new: &SyntaxElement) -> Option<SyntaxToken> {
+    let next = match &position.repr {
+        PositionRepr::FirstChild(parent) => parent.first_child_or_token()?,
+        PositionRepr::After(sibling) => sibling.next_sibling_or_token()?,
+    };
+    ws_between(new, &next)
+}
+fn ws_between(left: &SyntaxElement, right: &SyntaxElement) -> Option<SyntaxToken> {
+    if left.kind() == SyntaxKind::WHITESPACE || right.kind() == SyntaxKind::WHITESPACE {
+        return None;
+    }
+    if right.kind() == T![;] || right.kind() == T![,] {
+        return None;
+    }
+    if left.kind() == T![<] || right.kind() == T![>] {
+        return None;
+    }
+    if left.kind() == T![&] && right.kind() == SyntaxKind::LIFETIME {
+        return None;
+    }
+    if right.kind() == SyntaxKind::GENERIC_ARG_LIST {
+        return None;
+    }
+
+    if right.kind() == SyntaxKind::USE {
+        let mut indent = IndentLevel::from_element(left);
+        if left.kind() == SyntaxKind::USE {
+            indent.0 = IndentLevel::from_element(right).0.max(indent.0);
+        }
+        return Some(make::tokens::whitespace(&format!("\n{}", indent)));
+    }
+    Some(make::tokens::single_space())
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/tests.rs b/src/tools/rust-analyzer/crates/syntax/src/tests.rs
new file mode 100644
index 000000000..58fba8cfa
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/tests.rs
@@ -0,0 +1,186 @@
+#[cfg(not(feature = "in-rust-tree"))]
+mod ast_src;
+#[cfg(not(feature = "in-rust-tree"))]
+mod sourcegen_ast;
+
+use std::{
+    fs,
+    path::{Path, PathBuf},
+};
+
+use ast::HasName;
+use expect_test::expect_file;
+use rayon::prelude::*;
+use test_utils::{bench, bench_fixture, project_root};
+
+use crate::{ast, fuzz, AstNode, SourceFile, SyntaxError};
+
+#[test]
+fn parse_smoke_test() {
+    let code = r##"
+fn main() {
+    println!("Hello, world!")
+}
+    "##;
+
+    let parse = SourceFile::parse(code);
+    // eprintln!("{:#?}", parse.syntax_node());
+    assert!(parse.ok().is_ok());
+}
+
+#[test]
+fn benchmark_parser() {
+    if std::env::var("RUN_SLOW_BENCHES").is_err() {
+        return;
+    }
+
+    let data = bench_fixture::glorious_old_parser();
+    let tree = {
+        let _b = bench("parsing");
+        let p = SourceFile::parse(&data);
+        assert!(p.errors.is_empty());
+        assert_eq!(p.tree().syntax.text_range().len(), 352474.into());
+        p.tree()
+    };
+
+    {
+        let _b = bench("tree traversal");
+        let fn_names =
+            tree.syntax().descendants().filter_map(ast::Fn::cast).filter_map(|f| f.name()).count();
+        assert_eq!(fn_names, 268);
+    }
+}
+
+#[test]
+fn validation_tests() {
+    dir_tests(&test_data_dir(), &["parser/validation"], "rast", |text, path| {
+        let parse = SourceFile::parse(text);
+        let errors = parse.errors();
+        assert_errors_are_present(errors, path);
+        parse.debug_dump()
+    });
+}
+
+#[test]
+fn parser_fuzz_tests() {
+    for (_, text) in collect_rust_files(&test_data_dir(), &["parser/fuzz-failures"]) {
+        fuzz::check_parser(&text)
+    }
+}
+
+#[test]
+fn reparse_fuzz_tests() {
+    for (_, text) in collect_rust_files(&test_data_dir(), &["reparse/fuzz-failures"]) {
+        let check = fuzz::CheckReparse::from_data(text.as_bytes()).unwrap();
+        check.run();
+    }
+}
+
+/// Test that Rust-analyzer can parse and validate the rust-analyzer
+#[test]
+fn self_hosting_parsing() {
+    let crates_dir = project_root().join("crates");
+
+    let mut files = ::sourcegen::list_rust_files(&crates_dir);
+    files.retain(|path| {
+        // Get all files which are not in the crates/syntax/test_data folder
+        !path.components().any(|component| component.as_os_str() == "test_data")
+    });
+
+    assert!(
+        files.len() > 100,
+        "self_hosting_parsing found too few files - is it running in the right directory?"
+    );
+
+    let errors = files
+        .into_par_iter()
+        .filter_map(|file| {
+            let text = read_text(&file);
+            match SourceFile::parse(&text).ok() {
+                Ok(_) => None,
+                Err(err) => Some((file, err)),
+            }
+        })
+        .collect::<Vec<_>>();
+
+    if !errors.is_empty() {
+        let errors = errors
+            .into_iter()
+            .map(|(path, err)| format!("{}: {:?}\n", path.display(), err[0]))
+            .collect::<String>();
+        panic!("Parsing errors:\n{}\n", errors);
+    }
+}
+
+fn test_data_dir() -> PathBuf {
+    project_root().join("crates/syntax/test_data")
+}
+
+fn assert_errors_are_present(errors: &[SyntaxError], path: &Path) {
+    assert!(!errors.is_empty(), "There should be errors in the file {:?}", path.display());
+}
+
+/// Calls callback `f` with input code and file paths for each `.rs` file in `test_data_dir`
+/// subdirectories defined by `paths`.
+///
+/// If the content of the matching output file differs from the output of `f()`
+/// the test will fail.
+///
+/// If there is no matching output file it will be created and filled with the
+/// output of `f()`, but the test will fail.
+fn dir_tests<F>(test_data_dir: &Path, paths: &[&str], outfile_extension: &str, f: F)
+where
+    F: Fn(&str, &Path) -> String,
+{
+    for (path, input_code) in collect_rust_files(test_data_dir, paths) {
+        let actual = f(&input_code, &path);
+        let path = path.with_extension(outfile_extension);
+        expect_file![path].assert_eq(&actual)
+    }
+}
+
+/// Collects all `.rs` files from `dir` subdirectories defined by `paths`.
+fn collect_rust_files(root_dir: &Path, paths: &[&str]) -> Vec<(PathBuf, String)> {
+    paths
+        .iter()
+        .flat_map(|path| {
+            let path = root_dir.to_owned().join(path);
+            rust_files_in_dir(&path).into_iter()
+        })
+        .map(|path| {
+            let text = read_text(&path);
+            (path, text)
+        })
+        .collect()
+}
+
+/// Collects paths to all `.rs` files from `dir` in a sorted `Vec<PathBuf>`.
+fn rust_files_in_dir(dir: &Path) -> Vec<PathBuf> {
+    let mut acc = Vec::new();
+    for file in fs::read_dir(&dir).unwrap() {
+        let file = file.unwrap();
+        let path = file.path();
+        if path.extension().unwrap_or_default() == "rs" {
+            acc.push(path);
+        }
+    }
+    acc.sort();
+    acc
+}
+
+/// Read file and normalize newlines.
+///
+/// `rustc` seems to always normalize `\r\n` newlines to `\n`:
+///
+/// ```
+/// let s = "
+/// ";
+/// assert_eq!(s.as_bytes(), &[10]);
+/// ```
+///
+/// so this should always be correct.
+fn read_text(path: &Path) -> String {
+    fs::read_to_string(path)
+        .unwrap_or_else(|_| panic!("File at {:?} should be valid", path))
+        .replace("\r\n", "\n")
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/tests/ast_src.rs b/src/tools/rust-analyzer/crates/syntax/src/tests/ast_src.rs
new file mode 100644
index 000000000..cf5be1c30
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/tests/ast_src.rs
@@ -0,0 +1,252 @@
+//! Defines input for code generation process.
+
+pub(crate) struct KindsSrc<'a> {
+    pub(crate) punct: &'a [(&'a str, &'a str)],
+    pub(crate) keywords: &'a [&'a str],
+    pub(crate) contextual_keywords: &'a [&'a str],
+    pub(crate) literals: &'a [&'a str],
+    pub(crate) tokens: &'a [&'a str],
+    pub(crate) nodes: &'a [&'a str],
+}
+
+pub(crate) const KINDS_SRC: KindsSrc<'_> = KindsSrc {
+    punct: &[
+        (";", "SEMICOLON"),
+        (",", "COMMA"),
+        ("(", "L_PAREN"),
+        (")", "R_PAREN"),
+        ("{", "L_CURLY"),
+        ("}", "R_CURLY"),
+        ("[", "L_BRACK"),
+        ("]", "R_BRACK"),
+        ("<", "L_ANGLE"),
+        (">", "R_ANGLE"),
+        ("@", "AT"),
+        ("#", "POUND"),
+        ("~", "TILDE"),
+        ("?", "QUESTION"),
+        ("$", "DOLLAR"),
+        ("&", "AMP"),
+        ("|", "PIPE"),
+        ("+", "PLUS"),
+        ("*", "STAR"),
+        ("/", "SLASH"),
+        ("^", "CARET"),
+        ("%", "PERCENT"),
+        ("_", "UNDERSCORE"),
+        (".", "DOT"),
+        ("..", "DOT2"),
+        ("...", "DOT3"),
+        ("..=", "DOT2EQ"),
+        (":", "COLON"),
+        ("::", "COLON2"),
+        ("=", "EQ"),
+        ("==", "EQ2"),
+        ("=>", "FAT_ARROW"),
+        ("!", "BANG"),
+        ("!=", "NEQ"),
+        ("-", "MINUS"),
+        ("->", "THIN_ARROW"),
+        ("<=", "LTEQ"),
+        (">=", "GTEQ"),
+        ("+=", "PLUSEQ"),
+        ("-=", "MINUSEQ"),
+        ("|=", "PIPEEQ"),
+        ("&=", "AMPEQ"),
+        ("^=", "CARETEQ"),
+        ("/=", "SLASHEQ"),
+        ("*=", "STAREQ"),
+        ("%=", "PERCENTEQ"),
+        ("&&", "AMP2"),
+        ("||", "PIPE2"),
+        ("<<", "SHL"),
+        (">>", "SHR"),
+        ("<<=", "SHLEQ"),
+        (">>=", "SHREQ"),
+    ],
+    keywords: &[
+        "as", "async", "await", "box", "break", "const", "continue", "crate", "dyn", "else",
+        "enum", "extern", "false", "fn", "for", "if", "impl", "in", "let", "loop", "macro",
+        "match", "mod", "move", "mut", "pub", "ref", "return", "self", "Self", "static", "struct",
+        "super", "trait", "true", "try", "type", "unsafe", "use", "where", "while", "yield",
+    ],
+    contextual_keywords: &["auto", "default", "existential", "union", "raw", "macro_rules"],
+    literals: &["INT_NUMBER", "FLOAT_NUMBER", "CHAR", "BYTE", "STRING", "BYTE_STRING"],
+    tokens: &["ERROR", "IDENT", "WHITESPACE", "LIFETIME_IDENT", "COMMENT", "SHEBANG"],
+    nodes: &[
+        "SOURCE_FILE",
+        "STRUCT",
+        "UNION",
+        "ENUM",
+        "FN",
+        "RET_TYPE",
+        "EXTERN_CRATE",
+        "MODULE",
+        "USE",
+        "STATIC",
+        "CONST",
+        "TRAIT",
+        "IMPL",
+        "TYPE_ALIAS",
+        "MACRO_CALL",
+        "MACRO_RULES",
+        "MACRO_ARM",
+        "TOKEN_TREE",
+        "MACRO_DEF",
+        "PAREN_TYPE",
+        "TUPLE_TYPE",
+        "MACRO_TYPE",
+        "NEVER_TYPE",
+        "PATH_TYPE",
+        "PTR_TYPE",
+        "ARRAY_TYPE",
+        "SLICE_TYPE",
+        "REF_TYPE",
+        "INFER_TYPE",
+        "FN_PTR_TYPE",
+        "FOR_TYPE",
+        "IMPL_TRAIT_TYPE",
+        "DYN_TRAIT_TYPE",
+        "OR_PAT",
+        "PAREN_PAT",
+        "REF_PAT",
+        "BOX_PAT",
+        "IDENT_PAT",
+        "WILDCARD_PAT",
+        "REST_PAT",
+        "PATH_PAT",
+        "RECORD_PAT",
+        "RECORD_PAT_FIELD_LIST",
+        "RECORD_PAT_FIELD",
+        "TUPLE_STRUCT_PAT",
+        "TUPLE_PAT",
+        "SLICE_PAT",
+        "RANGE_PAT",
+        "LITERAL_PAT",
+        "MACRO_PAT",
+        "CONST_BLOCK_PAT",
+        // atoms
+        "TUPLE_EXPR",
+        "ARRAY_EXPR",
+        "PAREN_EXPR",
+        "PATH_EXPR",
+        "CLOSURE_EXPR",
+        "IF_EXPR",
+        "WHILE_EXPR",
+        "LOOP_EXPR",
+        "FOR_EXPR",
+        "CONTINUE_EXPR",
+        "BREAK_EXPR",
+        "LABEL",
+        "BLOCK_EXPR",
+        "STMT_LIST",
+        "RETURN_EXPR",
+        "YIELD_EXPR",
+        "LET_EXPR",
+        "UNDERSCORE_EXPR",
+        "MACRO_EXPR",
+        "MATCH_EXPR",
+        "MATCH_ARM_LIST",
+        "MATCH_ARM",
+        "MATCH_GUARD",
+        "RECORD_EXPR",
+        "RECORD_EXPR_FIELD_LIST",
+        "RECORD_EXPR_FIELD",
+        "BOX_EXPR",
+        // postfix
+        "CALL_EXPR",
+        "INDEX_EXPR",
+        "METHOD_CALL_EXPR",
+        "FIELD_EXPR",
+        "AWAIT_EXPR",
+        "TRY_EXPR",
+        "CAST_EXPR",
+        // unary
+        "REF_EXPR",
+        "PREFIX_EXPR",
+        "RANGE_EXPR", // just weird
+        "BIN_EXPR",
+        "EXTERN_BLOCK",
+        "EXTERN_ITEM_LIST",
+        "VARIANT",
+        "RECORD_FIELD_LIST",
+        "RECORD_FIELD",
+        "TUPLE_FIELD_LIST",
+        "TUPLE_FIELD",
+        "VARIANT_LIST",
+        "ITEM_LIST",
+        "ASSOC_ITEM_LIST",
+        "ATTR",
+        "META",
+        "USE_TREE",
+        "USE_TREE_LIST",
+        "PATH",
+        "PATH_SEGMENT",
+        "LITERAL",
+        "RENAME",
+        "VISIBILITY",
+        "WHERE_CLAUSE",
+        "WHERE_PRED",
+        "ABI",
+        "NAME",
+        "NAME_REF",
+        "LET_STMT",
+        "LET_ELSE",
+        "EXPR_STMT",
+        "GENERIC_PARAM_LIST",
+        "GENERIC_PARAM",
+        "LIFETIME_PARAM",
+        "TYPE_PARAM",
+        "CONST_PARAM",
+        "GENERIC_ARG_LIST",
+        "LIFETIME",
+        "LIFETIME_ARG",
+        "TYPE_ARG",
+        "ASSOC_TYPE_ARG",
+        "CONST_ARG",
+        "PARAM_LIST",
+        "PARAM",
+        "SELF_PARAM",
+        "ARG_LIST",
+        "TYPE_BOUND",
+        "TYPE_BOUND_LIST",
+        // macro related
+        "MACRO_ITEMS",
+        "MACRO_STMTS",
+    ],
+};
+
+#[derive(Default, Debug)]
+pub(crate) struct AstSrc {
+    pub(crate) tokens: Vec<String>,
+    pub(crate) nodes: Vec<AstNodeSrc>,
+    pub(crate) enums: Vec<AstEnumSrc>,
+}
+
+#[derive(Debug)]
+pub(crate) struct AstNodeSrc {
+    pub(crate) doc: Vec<String>,
+    pub(crate) name: String,
+    pub(crate) traits: Vec<String>,
+    pub(crate) fields: Vec<Field>,
+}
+
+#[derive(Debug, Eq, PartialEq)]
+pub(crate) enum Field {
+    Token(String),
+    Node { name: String, ty: String, cardinality: Cardinality },
+}
+
+#[derive(Debug, Eq, PartialEq)]
+pub(crate) enum Cardinality {
+    Optional,
+    Many,
+}
+
+#[derive(Debug)]
+pub(crate) struct AstEnumSrc {
+    pub(crate) doc: Vec<String>,
+    pub(crate) name: String,
+    pub(crate) traits: Vec<String>,
+    pub(crate) variants: Vec<String>,
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/tests/sourcegen_ast.rs b/src/tools/rust-analyzer/crates/syntax/src/tests/sourcegen_ast.rs
new file mode 100644
index 000000000..6d2766225
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/tests/sourcegen_ast.rs
@@ -0,0 +1,862 @@
+//! This module generates AST datatype used by rust-analyzer.
+//!
+//! Specifically, it generates the `SyntaxKind` enum and a number of newtype
+//! wrappers around `SyntaxNode` which implement `syntax::AstNode`.
+
+use std::{
+    collections::{BTreeSet, HashSet},
+    fmt::Write,
+};
+
+use itertools::Itertools;
+use proc_macro2::{Punct, Spacing};
+use quote::{format_ident, quote};
+use ungrammar::{Grammar, Rule};
+
+use crate::tests::ast_src::{
+    AstEnumSrc, AstNodeSrc, AstSrc, Cardinality, Field, KindsSrc, KINDS_SRC,
+};
+
+#[test]
+fn sourcegen_ast() {
+    let syntax_kinds = generate_syntax_kinds(KINDS_SRC);
+    let syntax_kinds_file =
+        sourcegen::project_root().join("crates/parser/src/syntax_kind/generated.rs");
+    sourcegen::ensure_file_contents(syntax_kinds_file.as_path(), &syntax_kinds);
+
+    let grammar =
+        include_str!(concat!(env!("CARGO_MANIFEST_DIR"), "/rust.ungram")).parse().unwrap();
+    let ast = lower(&grammar);
+
+    let ast_tokens = generate_tokens(&ast);
+    let ast_tokens_file =
+        sourcegen::project_root().join("crates/syntax/src/ast/generated/tokens.rs");
+    sourcegen::ensure_file_contents(ast_tokens_file.as_path(), &ast_tokens);
+
+    let ast_nodes = generate_nodes(KINDS_SRC, &ast);
+    let ast_nodes_file = sourcegen::project_root().join("crates/syntax/src/ast/generated/nodes.rs");
+    sourcegen::ensure_file_contents(ast_nodes_file.as_path(), &ast_nodes);
+}
+
+fn generate_tokens(grammar: &AstSrc) -> String {
+    let tokens = grammar.tokens.iter().map(|token| {
+        let name = format_ident!("{}", token);
+        let kind = format_ident!("{}", to_upper_snake_case(token));
+        quote! {
+            #[derive(Debug, Clone, PartialEq, Eq, Hash)]
+            pub struct #name {
+                pub(crate) syntax: SyntaxToken,
+            }
+            impl std::fmt::Display for #name {
+                fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+                    std::fmt::Display::fmt(&self.syntax, f)
+                }
+            }
+            impl AstToken for #name {
+                fn can_cast(kind: SyntaxKind) -> bool { kind == #kind }
+                fn cast(syntax: SyntaxToken) -> Option<Self> {
+                    if Self::can_cast(syntax.kind()) { Some(Self { syntax }) } else { None }
+                }
+                fn syntax(&self) -> &SyntaxToken { &self.syntax }
+            }
+        }
+    });
+
+    sourcegen::add_preamble(
+        "sourcegen_ast",
+        sourcegen::reformat(
+            quote! {
+                use crate::{SyntaxKind::{self, *}, SyntaxToken, ast::AstToken};
+                #(#tokens)*
+            }
+            .to_string(),
+        ),
+    )
+    .replace("#[derive", "\n#[derive")
+}
+
+fn generate_nodes(kinds: KindsSrc<'_>, grammar: &AstSrc) -> String {
+    let (node_defs, node_boilerplate_impls): (Vec<_>, Vec<_>) = grammar
+        .nodes
+        .iter()
+        .map(|node| {
+            let name = format_ident!("{}", node.name);
+            let kind = format_ident!("{}", to_upper_snake_case(&node.name));
+            let traits = node
+                .traits
+                .iter()
+                .filter(|trait_name| {
+                    // Loops have two expressions so this might collide, therefor manual impl it
+                    node.name != "ForExpr" && node.name != "WhileExpr"
+                        || trait_name.as_str() != "HasLoopBody"
+                })
+                .map(|trait_name| {
+                    let trait_name = format_ident!("{}", trait_name);
+                    quote!(impl ast::#trait_name for #name {})
+                });
+
+            let methods = node.fields.iter().map(|field| {
+                let method_name = field.method_name();
+                let ty = field.ty();
+
+                if field.is_many() {
+                    quote! {
+                        pub fn #method_name(&self) -> AstChildren<#ty> {
+                            support::children(&self.syntax)
+                        }
+                    }
+                } else if let Some(token_kind) = field.token_kind() {
+                    quote! {
+                        pub fn #method_name(&self) -> Option<#ty> {
+                            support::token(&self.syntax, #token_kind)
+                        }
+                    }
+                } else {
+                    quote! {
+                        pub fn #method_name(&self) -> Option<#ty> {
+                            support::child(&self.syntax)
+                        }
+                    }
+                }
+            });
+            (
+                quote! {
+                    #[pretty_doc_comment_placeholder_workaround]
+                    #[derive(Debug, Clone, PartialEq, Eq, Hash)]
+                    pub struct #name {
+                        pub(crate) syntax: SyntaxNode,
+                    }
+
+                    #(#traits)*
+
+                    impl #name {
+                        #(#methods)*
+                    }
+                },
+                quote! {
+                    impl AstNode for #name {
+                        fn can_cast(kind: SyntaxKind) -> bool {
+                            kind == #kind
+                        }
+                        fn cast(syntax: SyntaxNode) -> Option<Self> {
+                            if Self::can_cast(syntax.kind()) { Some(Self { syntax }) } else { None }
+                        }
+                        fn syntax(&self) -> &SyntaxNode { &self.syntax }
+                    }
+                },
+            )
+        })
+        .unzip();
+
+    let (enum_defs, enum_boilerplate_impls): (Vec<_>, Vec<_>) = grammar
+        .enums
+        .iter()
+        .map(|en| {
+            let variants: Vec<_> = en.variants.iter().map(|var| format_ident!("{}", var)).collect();
+            let name = format_ident!("{}", en.name);
+            let kinds: Vec<_> = variants
+                .iter()
+                .map(|name| format_ident!("{}", to_upper_snake_case(&name.to_string())))
+                .collect();
+            let traits = en.traits.iter().map(|trait_name| {
+                let trait_name = format_ident!("{}", trait_name);
+                quote!(impl ast::#trait_name for #name {})
+            });
+
+            let ast_node = if en.name == "Stmt" {
+                quote! {}
+            } else {
+                quote! {
+                    impl AstNode for #name {
+                        fn can_cast(kind: SyntaxKind) -> bool {
+                            match kind {
+                                #(#kinds)|* => true,
+                                _ => false,
+                            }
+                        }
+                        fn cast(syntax: SyntaxNode) -> Option<Self> {
+                            let res = match syntax.kind() {
+                                #(
+                                #kinds => #name::#variants(#variants { syntax }),
+                                )*
+                                _ => return None,
+                            };
+                            Some(res)
+                        }
+                        fn syntax(&self) -> &SyntaxNode {
+                            match self {
+                                #(
+                                #name::#variants(it) => &it.syntax,
+                                )*
+                            }
+                        }
+                    }
+                }
+            };
+
+            (
+                quote! {
+                    #[pretty_doc_comment_placeholder_workaround]
+                    #[derive(Debug, Clone, PartialEq, Eq, Hash)]
+                    pub enum #name {
+                        #(#variants(#variants),)*
+                    }
+
+                    #(#traits)*
+                },
+                quote! {
+                    #(
+                        impl From<#variants> for #name {
+                            fn from(node: #variants) -> #name {
+                                #name::#variants(node)
+                            }
+                        }
+                    )*
+                    #ast_node
+                },
+            )
+        })
+        .unzip();
+
+    let (any_node_defs, any_node_boilerplate_impls): (Vec<_>, Vec<_>) = grammar
+        .nodes
+        .iter()
+        .flat_map(|node| node.traits.iter().map(move |t| (t, node)))
+        .into_group_map()
+        .into_iter()
+        .sorted_by_key(|(k, _)| *k)
+        .map(|(trait_name, nodes)| {
+            let name = format_ident!("Any{}", trait_name);
+            let trait_name = format_ident!("{}", trait_name);
+            let kinds: Vec<_> = nodes
+                .iter()
+                .map(|name| format_ident!("{}", to_upper_snake_case(&name.name.to_string())))
+                .collect();
+
+            (
+                quote! {
+                    #[pretty_doc_comment_placeholder_workaround]
+                    #[derive(Debug, Clone, PartialEq, Eq, Hash)]
+                    pub struct #name {
+                        pub(crate) syntax: SyntaxNode,
+                    }
+                    impl ast::#trait_name for #name {}
+                },
+                quote! {
+                    impl #name {
+                        #[inline]
+                        pub fn new<T: ast::#trait_name>(node: T) -> #name {
+                            #name {
+                                syntax: node.syntax().clone()
+                            }
+                        }
+                    }
+                    impl AstNode for #name {
+                        fn can_cast(kind: SyntaxKind) -> bool {
+                            match kind {
+                                #(#kinds)|* => true,
+                                _ => false,
+                            }
+                        }
+                        fn cast(syntax: SyntaxNode) -> Option<Self> {
+                            Self::can_cast(syntax.kind()).then(|| #name { syntax })
+                        }
+                        fn syntax(&self) -> &SyntaxNode {
+                            &self.syntax
+                        }
+                    }
+                },
+            )
+        })
+        .unzip();
+
+    let enum_names = grammar.enums.iter().map(|it| &it.name);
+    let node_names = grammar.nodes.iter().map(|it| &it.name);
+
+    let display_impls =
+        enum_names.chain(node_names.clone()).map(|it| format_ident!("{}", it)).map(|name| {
+            quote! {
+                impl std::fmt::Display for #name {
+                    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+                        std::fmt::Display::fmt(self.syntax(), f)
+                    }
+                }
+            }
+        });
+
+    let defined_nodes: HashSet<_> = node_names.collect();
+
+    for node in kinds
+        .nodes
+        .iter()
+        .map(|kind| to_pascal_case(kind))
+        .filter(|name| !defined_nodes.iter().any(|&it| it == name))
+    {
+        drop(node)
+        // FIXME: restore this
+        // eprintln!("Warning: node {} not defined in ast source", node);
+    }
+
+    let ast = quote! {
+        #![allow(non_snake_case)]
+        use crate::{
+            SyntaxNode, SyntaxToken, SyntaxKind::{self, *},
+            ast::{self, AstNode, AstChildren, support},
+            T,
+        };
+
+        #(#node_defs)*
+        #(#enum_defs)*
+        #(#any_node_defs)*
+        #(#node_boilerplate_impls)*
+        #(#enum_boilerplate_impls)*
+        #(#any_node_boilerplate_impls)*
+        #(#display_impls)*
+    };
+
+    let ast = ast.to_string().replace("T ! [", "T![");
+
+    let mut res = String::with_capacity(ast.len() * 2);
+
+    let mut docs =
+        grammar.nodes.iter().map(|it| &it.doc).chain(grammar.enums.iter().map(|it| &it.doc));
+
+    for chunk in ast.split("# [pretty_doc_comment_placeholder_workaround] ") {
+        res.push_str(chunk);
+        if let Some(doc) = docs.next() {
+            write_doc_comment(doc, &mut res);
+        }
+    }
+
+    let res = sourcegen::add_preamble("sourcegen_ast", sourcegen::reformat(res));
+    res.replace("#[derive", "\n#[derive")
+}
+
+fn write_doc_comment(contents: &[String], dest: &mut String) {
+    for line in contents {
+        writeln!(dest, "///{}", line).unwrap();
+    }
+}
+
+fn generate_syntax_kinds(grammar: KindsSrc<'_>) -> String {
+    let (single_byte_tokens_values, single_byte_tokens): (Vec<_>, Vec<_>) = grammar
+        .punct
+        .iter()
+        .filter(|(token, _name)| token.len() == 1)
+        .map(|(token, name)| (token.chars().next().unwrap(), format_ident!("{}", name)))
+        .unzip();
+
+    let punctuation_values = grammar.punct.iter().map(|(token, _name)| {
+        if "{}[]()".contains(token) {
+            let c = token.chars().next().unwrap();
+            quote! { #c }
+        } else {
+            let cs = token.chars().map(|c| Punct::new(c, Spacing::Joint));
+            quote! { #(#cs)* }
+        }
+    });
+    let punctuation =
+        grammar.punct.iter().map(|(_token, name)| format_ident!("{}", name)).collect::<Vec<_>>();
+
+    let x = |&name| match name {
+        "Self" => format_ident!("SELF_TYPE_KW"),
+        name => format_ident!("{}_KW", to_upper_snake_case(name)),
+    };
+    let full_keywords_values = grammar.keywords;
+    let full_keywords = full_keywords_values.iter().map(x);
+
+    let contextual_keywords_values = &grammar.contextual_keywords;
+    let contextual_keywords = contextual_keywords_values.iter().map(x);
+
+    let all_keywords_values = grammar
+        .keywords
+        .iter()
+        .chain(grammar.contextual_keywords.iter())
+        .copied()
+        .collect::<Vec<_>>();
+    let all_keywords_idents = all_keywords_values.iter().map(|kw| format_ident!("{}", kw));
+    let all_keywords = all_keywords_values.iter().map(x).collect::<Vec<_>>();
+
+    let literals =
+        grammar.literals.iter().map(|name| format_ident!("{}", name)).collect::<Vec<_>>();
+
+    let tokens = grammar.tokens.iter().map(|name| format_ident!("{}", name)).collect::<Vec<_>>();
+
+    let nodes = grammar.nodes.iter().map(|name| format_ident!("{}", name)).collect::<Vec<_>>();
+
+    let ast = quote! {
+        #![allow(bad_style, missing_docs, unreachable_pub)]
+        /// The kind of syntax node, e.g. `IDENT`, `USE_KW`, or `STRUCT`.
+        #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
+        #[repr(u16)]
+        pub enum SyntaxKind {
+            // Technical SyntaxKinds: they appear temporally during parsing,
+            // but never end up in the final tree
+            #[doc(hidden)]
+            TOMBSTONE,
+            #[doc(hidden)]
+            EOF,
+            #(#punctuation,)*
+            #(#all_keywords,)*
+            #(#literals,)*
+            #(#tokens,)*
+            #(#nodes,)*
+
+            // Technical kind so that we can cast from u16 safely
+            #[doc(hidden)]
+            __LAST,
+        }
+        use self::SyntaxKind::*;
+
+        impl SyntaxKind {
+            pub fn is_keyword(self) -> bool {
+                match self {
+                    #(#all_keywords)|* => true,
+                    _ => false,
+                }
+            }
+
+            pub fn is_punct(self) -> bool {
+                match self {
+                    #(#punctuation)|* => true,
+                    _ => false,
+                }
+            }
+
+            pub fn is_literal(self) -> bool {
+                match self {
+                    #(#literals)|* => true,
+                    _ => false,
+                }
+            }
+
+            pub fn from_keyword(ident: &str) -> Option<SyntaxKind> {
+                let kw = match ident {
+                    #(#full_keywords_values => #full_keywords,)*
+                    _ => return None,
+                };
+                Some(kw)
+            }
+
+            pub fn from_contextual_keyword(ident: &str) -> Option<SyntaxKind> {
+                let kw = match ident {
+                    #(#contextual_keywords_values => #contextual_keywords,)*
+                    _ => return None,
+                };
+                Some(kw)
+            }
+
+            pub fn from_char(c: char) -> Option<SyntaxKind> {
+                let tok = match c {
+                    #(#single_byte_tokens_values => #single_byte_tokens,)*
+                    _ => return None,
+                };
+                Some(tok)
+            }
+        }
+
+        #[macro_export]
+        macro_rules! T {
+            #([#punctuation_values] => { $crate::SyntaxKind::#punctuation };)*
+            #([#all_keywords_idents] => { $crate::SyntaxKind::#all_keywords };)*
+            [lifetime_ident] => { $crate::SyntaxKind::LIFETIME_IDENT };
+            [ident] => { $crate::SyntaxKind::IDENT };
+            [shebang] => { $crate::SyntaxKind::SHEBANG };
+        }
+        pub use T;
+    };
+
+    sourcegen::add_preamble("sourcegen_ast", sourcegen::reformat(ast.to_string()))
+}
+
+fn to_upper_snake_case(s: &str) -> String {
+    let mut buf = String::with_capacity(s.len());
+    let mut prev = false;
+    for c in s.chars() {
+        if c.is_ascii_uppercase() && prev {
+            buf.push('_')
+        }
+        prev = true;
+
+        buf.push(c.to_ascii_uppercase());
+    }
+    buf
+}
+
+fn to_lower_snake_case(s: &str) -> String {
+    let mut buf = String::with_capacity(s.len());
+    let mut prev = false;
+    for c in s.chars() {
+        if c.is_ascii_uppercase() && prev {
+            buf.push('_')
+        }
+        prev = true;
+
+        buf.push(c.to_ascii_lowercase());
+    }
+    buf
+}
+
+fn to_pascal_case(s: &str) -> String {
+    let mut buf = String::with_capacity(s.len());
+    let mut prev_is_underscore = true;
+    for c in s.chars() {
+        if c == '_' {
+            prev_is_underscore = true;
+        } else if prev_is_underscore {
+            buf.push(c.to_ascii_uppercase());
+            prev_is_underscore = false;
+        } else {
+            buf.push(c.to_ascii_lowercase());
+        }
+    }
+    buf
+}
+
+fn pluralize(s: &str) -> String {
+    format!("{}s", s)
+}
+
+impl Field {
+    fn is_many(&self) -> bool {
+        matches!(self, Field::Node { cardinality: Cardinality::Many, .. })
+    }
+    fn token_kind(&self) -> Option<proc_macro2::TokenStream> {
+        match self {
+            Field::Token(token) => {
+                let token: proc_macro2::TokenStream = token.parse().unwrap();
+                Some(quote! { T![#token] })
+            }
+            _ => None,
+        }
+    }
+    fn method_name(&self) -> proc_macro2::Ident {
+        match self {
+            Field::Token(name) => {
+                let name = match name.as_str() {
+                    ";" => "semicolon",
+                    "->" => "thin_arrow",
+                    "'{'" => "l_curly",
+                    "'}'" => "r_curly",
+                    "'('" => "l_paren",
+                    "')'" => "r_paren",
+                    "'['" => "l_brack",
+                    "']'" => "r_brack",
+                    "<" => "l_angle",
+                    ">" => "r_angle",
+                    "=" => "eq",
+                    "!" => "excl",
+                    "*" => "star",
+                    "&" => "amp",
+                    "_" => "underscore",
+                    "." => "dot",
+                    ".." => "dotdot",
+                    "..." => "dotdotdot",
+                    "..=" => "dotdoteq",
+                    "=>" => "fat_arrow",
+                    "@" => "at",
+                    ":" => "colon",
+                    "::" => "coloncolon",
+                    "#" => "pound",
+                    "?" => "question_mark",
+                    "," => "comma",
+                    "|" => "pipe",
+                    "~" => "tilde",
+                    _ => name,
+                };
+                format_ident!("{}_token", name)
+            }
+            Field::Node { name, .. } => {
+                if name == "type" {
+                    format_ident!("ty")
+                } else {
+                    format_ident!("{}", name)
+                }
+            }
+        }
+    }
+    fn ty(&self) -> proc_macro2::Ident {
+        match self {
+            Field::Token(_) => format_ident!("SyntaxToken"),
+            Field::Node { ty, .. } => format_ident!("{}", ty),
+        }
+    }
+}
+
+fn lower(grammar: &Grammar) -> AstSrc {
+    let mut res = AstSrc {
+        tokens: "Whitespace Comment String ByteString IntNumber FloatNumber Char Byte Ident"
+            .split_ascii_whitespace()
+            .map(|it| it.to_string())
+            .collect::<Vec<_>>(),
+        ..Default::default()
+    };
+
+    let nodes = grammar.iter().collect::<Vec<_>>();
+
+    for &node in &nodes {
+        let name = grammar[node].name.clone();
+        let rule = &grammar[node].rule;
+        match lower_enum(grammar, rule) {
+            Some(variants) => {
+                let enum_src = AstEnumSrc { doc: Vec::new(), name, traits: Vec::new(), variants };
+                res.enums.push(enum_src);
+            }
+            None => {
+                let mut fields = Vec::new();
+                lower_rule(&mut fields, grammar, None, rule);
+                res.nodes.push(AstNodeSrc { doc: Vec::new(), name, traits: Vec::new(), fields });
+            }
+        }
+    }
+
+    deduplicate_fields(&mut res);
+    extract_enums(&mut res);
+    extract_struct_traits(&mut res);
+    extract_enum_traits(&mut res);
+    res
+}
+
+fn lower_enum(grammar: &Grammar, rule: &Rule) -> Option<Vec<String>> {
+    let alternatives = match rule {
+        Rule::Alt(it) => it,
+        _ => return None,
+    };
+    let mut variants = Vec::new();
+    for alternative in alternatives {
+        match alternative {
+            Rule::Node(it) => variants.push(grammar[*it].name.clone()),
+            Rule::Token(it) if grammar[*it].name == ";" => (),
+            _ => return None,
+        }
+    }
+    Some(variants)
+}
+
+fn lower_rule(acc: &mut Vec<Field>, grammar: &Grammar, label: Option<&String>, rule: &Rule) {
+    if lower_comma_list(acc, grammar, label, rule) {
+        return;
+    }
+
+    match rule {
+        Rule::Node(node) => {
+            let ty = grammar[*node].name.clone();
+            let name = label.cloned().unwrap_or_else(|| to_lower_snake_case(&ty));
+            let field = Field::Node { name, ty, cardinality: Cardinality::Optional };
+            acc.push(field);
+        }
+        Rule::Token(token) => {
+            assert!(label.is_none());
+            let mut name = grammar[*token].name.clone();
+            if name != "int_number" && name != "string" {
+                if "[]{}()".contains(&name) {
+                    name = format!("'{}'", name);
+                }
+                let field = Field::Token(name);
+                acc.push(field);
+            }
+        }
+        Rule::Rep(inner) => {
+            if let Rule::Node(node) = &**inner {
+                let ty = grammar[*node].name.clone();
+                let name = label.cloned().unwrap_or_else(|| pluralize(&to_lower_snake_case(&ty)));
+                let field = Field::Node { name, ty, cardinality: Cardinality::Many };
+                acc.push(field);
+                return;
+            }
+            panic!("unhandled rule: {:?}", rule)
+        }
+        Rule::Labeled { label: l, rule } => {
+            assert!(label.is_none());
+            let manually_implemented = matches!(
+                l.as_str(),
+                "lhs"
+                    | "rhs"
+                    | "then_branch"
+                    | "else_branch"
+                    | "start"
+                    | "end"
+                    | "op"
+                    | "index"
+                    | "base"
+                    | "value"
+                    | "trait"
+                    | "self_ty"
+                    | "iterable"
+                    | "condition"
+            );
+            if manually_implemented {
+                return;
+            }
+            lower_rule(acc, grammar, Some(l), rule);
+        }
+        Rule::Seq(rules) | Rule::Alt(rules) => {
+            for rule in rules {
+                lower_rule(acc, grammar, label, rule)
+            }
+        }
+        Rule::Opt(rule) => lower_rule(acc, grammar, label, rule),
+    }
+}
+
+// (T (',' T)* ','?)
+fn lower_comma_list(
+    acc: &mut Vec<Field>,
+    grammar: &Grammar,
+    label: Option<&String>,
+    rule: &Rule,
+) -> bool {
+    let rule = match rule {
+        Rule::Seq(it) => it,
+        _ => return false,
+    };
+    let (node, repeat, trailing_comma) = match rule.as_slice() {
+        [Rule::Node(node), Rule::Rep(repeat), Rule::Opt(trailing_comma)] => {
+            (node, repeat, trailing_comma)
+        }
+        _ => return false,
+    };
+    let repeat = match &**repeat {
+        Rule::Seq(it) => it,
+        _ => return false,
+    };
+    match repeat.as_slice() {
+        [comma, Rule::Node(n)] if comma == &**trailing_comma && n == node => (),
+        _ => return false,
+    }
+    let ty = grammar[*node].name.clone();
+    let name = label.cloned().unwrap_or_else(|| pluralize(&to_lower_snake_case(&ty)));
+    let field = Field::Node { name, ty, cardinality: Cardinality::Many };
+    acc.push(field);
+    true
+}
+
+fn deduplicate_fields(ast: &mut AstSrc) {
+    for node in &mut ast.nodes {
+        let mut i = 0;
+        'outer: while i < node.fields.len() {
+            for j in 0..i {
+                let f1 = &node.fields[i];
+                let f2 = &node.fields[j];
+                if f1 == f2 {
+                    node.fields.remove(i);
+                    continue 'outer;
+                }
+            }
+            i += 1;
+        }
+    }
+}
+
+fn extract_enums(ast: &mut AstSrc) {
+    for node in &mut ast.nodes {
+        for enm in &ast.enums {
+            let mut to_remove = Vec::new();
+            for (i, field) in node.fields.iter().enumerate() {
+                let ty = field.ty().to_string();
+                if enm.variants.iter().any(|it| it == &ty) {
+                    to_remove.push(i);
+                }
+            }
+            if to_remove.len() == enm.variants.len() {
+                node.remove_field(to_remove);
+                let ty = enm.name.clone();
+                let name = to_lower_snake_case(&ty);
+                node.fields.push(Field::Node { name, ty, cardinality: Cardinality::Optional });
+            }
+        }
+    }
+}
+
+fn extract_struct_traits(ast: &mut AstSrc) {
+    let traits: &[(&str, &[&str])] = &[
+        ("HasAttrs", &["attrs"]),
+        ("HasName", &["name"]),
+        ("HasVisibility", &["visibility"]),
+        ("HasGenericParams", &["generic_param_list", "where_clause"]),
+        ("HasTypeBounds", &["type_bound_list", "colon_token"]),
+        ("HasModuleItem", &["items"]),
+        ("HasLoopBody", &["label", "loop_body"]),
+        ("HasArgList", &["arg_list"]),
+    ];
+
+    for node in &mut ast.nodes {
+        for (name, methods) in traits {
+            extract_struct_trait(node, name, methods);
+        }
+    }
+
+    let nodes_with_doc_comments = [
+        "SourceFile",
+        "Fn",
+        "Struct",
+        "Union",
+        "RecordField",
+        "TupleField",
+        "Enum",
+        "Variant",
+        "Trait",
+        "Module",
+        "Static",
+        "Const",
+        "TypeAlias",
+        "Impl",
+        "ExternBlock",
+        "ExternCrate",
+        "MacroCall",
+        "MacroRules",
+        "MacroDef",
+        "Use",
+    ];
+
+    for node in &mut ast.nodes {
+        if nodes_with_doc_comments.contains(&&*node.name) {
+            node.traits.push("HasDocComments".into());
+        }
+    }
+}
+
+fn extract_struct_trait(node: &mut AstNodeSrc, trait_name: &str, methods: &[&str]) {
+    let mut to_remove = Vec::new();
+    for (i, field) in node.fields.iter().enumerate() {
+        let method_name = field.method_name().to_string();
+        if methods.iter().any(|&it| it == method_name) {
+            to_remove.push(i);
+        }
+    }
+    if to_remove.len() == methods.len() {
+        node.traits.push(trait_name.to_string());
+        node.remove_field(to_remove);
+    }
+}
+
+fn extract_enum_traits(ast: &mut AstSrc) {
+    for enm in &mut ast.enums {
+        if enm.name == "Stmt" {
+            continue;
+        }
+        let nodes = &ast.nodes;
+        let mut variant_traits = enm
+            .variants
+            .iter()
+            .map(|var| nodes.iter().find(|it| &it.name == var).unwrap())
+            .map(|node| node.traits.iter().cloned().collect::<BTreeSet<_>>());
+
+        let mut enum_traits = match variant_traits.next() {
+            Some(it) => it,
+            None => continue,
+        };
+        for traits in variant_traits {
+            enum_traits = enum_traits.intersection(&traits).cloned().collect();
+        }
+        enm.traits = enum_traits.into_iter().collect();
+    }
+}
+
+impl AstNodeSrc {
+    fn remove_field(&mut self, to_remove: Vec<usize>) {
+        to_remove.into_iter().rev().for_each(|idx| {
+            self.fields.remove(idx);
+        });
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/token_text.rs b/src/tools/rust-analyzer/crates/syntax/src/token_text.rs
new file mode 100644
index 000000000..913b24d42
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/token_text.rs
@@ -0,0 +1,95 @@
+//! Yet another version of owned string, backed by a syntax tree token.
+
+use std::{cmp::Ordering, fmt, ops};
+
+use rowan::GreenToken;
+
+pub struct TokenText<'a>(pub(crate) Repr<'a>);
+
+pub(crate) enum Repr<'a> {
+    Borrowed(&'a str),
+    Owned(GreenToken),
+}
+
+impl<'a> TokenText<'a> {
+    pub(crate) fn borrowed(text: &'a str) -> Self {
+        TokenText(Repr::Borrowed(text))
+    }
+
+    pub(crate) fn owned(green: GreenToken) -> Self {
+        TokenText(Repr::Owned(green))
+    }
+
+    pub fn as_str(&self) -> &str {
+        match &self.0 {
+            &Repr::Borrowed(it) => it,
+            Repr::Owned(green) => green.text(),
+        }
+    }
+}
+
+impl ops::Deref for TokenText<'_> {
+    type Target = str;
+
+    fn deref(&self) -> &str {
+        self.as_str()
+    }
+}
+impl AsRef<str> for TokenText<'_> {
+    fn as_ref(&self) -> &str {
+        self.as_str()
+    }
+}
+
+impl From<TokenText<'_>> for String {
+    fn from(token_text: TokenText<'_>) -> Self {
+        token_text.as_str().into()
+    }
+}
+
+impl PartialEq<&'_ str> for TokenText<'_> {
+    fn eq(&self, other: &&str) -> bool {
+        self.as_str() == *other
+    }
+}
+impl PartialEq<TokenText<'_>> for &'_ str {
+    fn eq(&self, other: &TokenText<'_>) -> bool {
+        other == self
+    }
+}
+impl PartialEq<String> for TokenText<'_> {
+    fn eq(&self, other: &String) -> bool {
+        self.as_str() == other.as_str()
+    }
+}
+impl PartialEq<TokenText<'_>> for String {
+    fn eq(&self, other: &TokenText<'_>) -> bool {
+        other == self
+    }
+}
+impl PartialEq for TokenText<'_> {
+    fn eq(&self, other: &TokenText<'_>) -> bool {
+        self.as_str() == other.as_str()
+    }
+}
+impl Eq for TokenText<'_> {}
+impl Ord for TokenText<'_> {
+    fn cmp(&self, other: &Self) -> Ordering {
+        self.as_str().cmp(other.as_str())
+    }
+}
+impl PartialOrd for TokenText<'_> {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        Some(self.cmp(other))
+    }
+}
+impl fmt::Display for TokenText<'_> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt::Display::fmt(self.as_str(), f)
+    }
+}
+impl fmt::Debug for TokenText<'_> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt::Debug::fmt(self.as_str(), f)
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/utils.rs b/src/tools/rust-analyzer/crates/syntax/src/utils.rs
new file mode 100644
index 000000000..f4c02518b
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/utils.rs
@@ -0,0 +1,43 @@
+//! A set of utils methods to reuse on other abstraction levels
+
+use itertools::Itertools;
+
+use crate::{ast, match_ast, AstNode};
+
+pub fn path_to_string_stripping_turbo_fish(path: &ast::Path) -> String {
+    path.syntax()
+        .children()
+        .filter_map(|node| {
+            match_ast! {
+                match node {
+                    ast::PathSegment(it) => {
+                        Some(it.name_ref()?.to_string())
+                    },
+                    ast::Path(it) => {
+                        Some(path_to_string_stripping_turbo_fish(&it))
+                    },
+                    _ => None,
+                }
+            }
+        })
+        .join("::")
+}
+
+#[cfg(test)]
+mod tests {
+    use super::path_to_string_stripping_turbo_fish;
+    use crate::ast::make;
+
+    #[test]
+    fn turbofishes_are_stripped() {
+        assert_eq!("Vec", path_to_string_stripping_turbo_fish(&make::path_from_text("Vec::<i32>")),);
+        assert_eq!(
+            "Vec::new",
+            path_to_string_stripping_turbo_fish(&make::path_from_text("Vec::<i32>::new")),
+        );
+        assert_eq!(
+            "Vec::new",
+            path_to_string_stripping_turbo_fish(&make::path_from_text("Vec::new()")),
+        );
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/validation.rs b/src/tools/rust-analyzer/crates/syntax/src/validation.rs
new file mode 100644
index 000000000..b9f2b5132
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/validation.rs
@@ -0,0 +1,378 @@
+//! This module implements syntax validation that the parser doesn't handle.
+//!
+//! A failed validation emits a diagnostic.
+
+mod block;
+
+use rowan::Direction;
+use rustc_lexer::unescape::{
+    self, unescape_byte, unescape_byte_literal, unescape_char, unescape_literal, Mode,
+};
+
+use crate::{
+    algo,
+    ast::{self, HasAttrs, HasVisibility},
+    match_ast, AstNode, SyntaxError,
+    SyntaxKind::{CONST, FN, INT_NUMBER, TYPE_ALIAS},
+    SyntaxNode, SyntaxToken, TextSize, T,
+};
+
+pub(crate) fn validate(root: &SyntaxNode) -> Vec<SyntaxError> {
+    // FIXME:
+    // * Add unescape validation of raw string literals and raw byte string literals
+    // * Add validation of doc comments are being attached to nodes
+
+    let mut errors = Vec::new();
+    for node in root.descendants() {
+        match_ast! {
+            match node {
+                ast::Literal(it) => validate_literal(it, &mut errors),
+                ast::Const(it) => validate_const(it, &mut errors),
+                ast::BlockExpr(it) => block::validate_block_expr(it, &mut errors),
+                ast::FieldExpr(it) => validate_numeric_name(it.name_ref(), &mut errors),
+                ast::RecordExprField(it) => validate_numeric_name(it.name_ref(), &mut errors),
+                ast::Visibility(it) => validate_visibility(it, &mut errors),
+                ast::RangeExpr(it) => validate_range_expr(it, &mut errors),
+                ast::PathSegment(it) => validate_path_keywords(it, &mut errors),
+                ast::RefType(it) => validate_trait_object_ref_ty(it, &mut errors),
+                ast::PtrType(it) => validate_trait_object_ptr_ty(it, &mut errors),
+                ast::FnPtrType(it) => validate_trait_object_fn_ptr_ret_ty(it, &mut errors),
+                ast::MacroRules(it) => validate_macro_rules(it, &mut errors),
+                ast::LetExpr(it) => validate_let_expr(it, &mut errors),
+                _ => (),
+            }
+        }
+    }
+    errors
+}
+
+fn rustc_unescape_error_to_string(err: unescape::EscapeError) -> &'static str {
+    use unescape::EscapeError as EE;
+
+    #[rustfmt::skip]
+    let err_message = match err {
+        EE::ZeroChars => {
+            "Literal must not be empty"
+        }
+        EE::MoreThanOneChar => {
+            "Literal must be one character long"
+        }
+        EE::LoneSlash => {
+            "Character must be escaped: `\\`"
+        }
+        EE::InvalidEscape => {
+            "Invalid escape"
+        }
+        EE::BareCarriageReturn | EE::BareCarriageReturnInRawString => {
+            "Character must be escaped: `\r`"
+        }
+        EE::EscapeOnlyChar => {
+            "Escape character `\\` must be escaped itself"
+        }
+        EE::TooShortHexEscape => {
+            "ASCII hex escape code must have exactly two digits"
+        }
+        EE::InvalidCharInHexEscape => {
+            "ASCII hex escape code must contain only hex characters"
+        }
+        EE::OutOfRangeHexEscape => {
+            "ASCII hex escape code must be at most 0x7F"
+        }
+        EE::NoBraceInUnicodeEscape => {
+            "Missing `{` to begin the unicode escape"
+        }
+        EE::InvalidCharInUnicodeEscape => {
+            "Unicode escape must contain only hex characters and underscores"
+        }
+        EE::EmptyUnicodeEscape => {
+            "Unicode escape must not be empty"
+        }
+        EE::UnclosedUnicodeEscape => {
+            "Missing `}` to terminate the unicode escape"
+        }
+        EE::LeadingUnderscoreUnicodeEscape => {
+            "Unicode escape code must not begin with an underscore"
+        }
+        EE::OverlongUnicodeEscape => {
+            "Unicode escape code must have at most 6 digits"
+        }
+        EE::LoneSurrogateUnicodeEscape => {
+            "Unicode escape code must not be a surrogate"
+        }
+        EE::OutOfRangeUnicodeEscape => {
+            "Unicode escape code must be at most 0x10FFFF"
+        }
+        EE::UnicodeEscapeInByte => {
+            "Byte literals must not contain unicode escapes"
+        }
+        EE::NonAsciiCharInByte | EE::NonAsciiCharInByteString => {
+            "Byte literals must not contain non-ASCII characters"
+        }
+    };
+
+    err_message
+}
+
+fn validate_literal(literal: ast::Literal, acc: &mut Vec<SyntaxError>) {
+    // FIXME: move this function to outer scope (https://github.com/rust-lang/rust-analyzer/pull/2834#discussion_r366196658)
+    fn unquote(text: &str, prefix_len: usize, end_delimiter: char) -> Option<&str> {
+        text.rfind(end_delimiter).and_then(|end| text.get(prefix_len..end))
+    }
+
+    let token = literal.token();
+    let text = token.text();
+
+    // FIXME: lift this lambda refactor to `fn` (https://github.com/rust-lang/rust-analyzer/pull/2834#discussion_r366199205)
+    let mut push_err = |prefix_len, (off, err): (usize, unescape::EscapeError)| {
+        let off = token.text_range().start() + TextSize::try_from(off + prefix_len).unwrap();
+        acc.push(SyntaxError::new_at_offset(rustc_unescape_error_to_string(err), off));
+    };
+
+    match literal.kind() {
+        ast::LiteralKind::String(s) => {
+            if !s.is_raw() {
+                if let Some(without_quotes) = unquote(text, 1, '"') {
+                    unescape_literal(without_quotes, Mode::Str, &mut |range, char| {
+                        if let Err(err) = char {
+                            push_err(1, (range.start, err));
+                        }
+                    });
+                }
+            }
+        }
+        ast::LiteralKind::ByteString(s) => {
+            if !s.is_raw() {
+                if let Some(without_quotes) = unquote(text, 2, '"') {
+                    unescape_byte_literal(without_quotes, Mode::ByteStr, &mut |range, char| {
+                        if let Err(err) = char {
+                            push_err(2, (range.start, err));
+                        }
+                    });
+                }
+            }
+        }
+        ast::LiteralKind::Char(_) => {
+            if let Some(Err(e)) = unquote(text, 1, '\'').map(unescape_char) {
+                push_err(1, e);
+            }
+        }
+        ast::LiteralKind::Byte(_) => {
+            if let Some(Err(e)) = unquote(text, 2, '\'').map(unescape_byte) {
+                push_err(2, e);
+            }
+        }
+        ast::LiteralKind::IntNumber(_)
+        | ast::LiteralKind::FloatNumber(_)
+        | ast::LiteralKind::Bool(_) => {}
+    }
+}
+
+pub(crate) fn validate_block_structure(root: &SyntaxNode) {
+    let mut stack = Vec::new();
+    for node in root.descendants_with_tokens() {
+        match node.kind() {
+            T!['{'] => stack.push(node),
+            T!['}'] => {
+                if let Some(pair) = stack.pop() {
+                    assert_eq!(
+                        node.parent(),
+                        pair.parent(),
+                        "\nunpaired curlys:\n{}\n{:#?}\n",
+                        root.text(),
+                        root,
+                    );
+                    assert!(
+                        node.next_sibling_or_token().is_none()
+                            && pair.prev_sibling_or_token().is_none(),
+                        "\nfloating curlys at {:?}\nfile:\n{}\nerror:\n{}\n",
+                        node,
+                        root.text(),
+                        node,
+                    );
+                }
+            }
+            _ => (),
+        }
+    }
+}
+
+fn validate_numeric_name(name_ref: Option<ast::NameRef>, errors: &mut Vec<SyntaxError>) {
+    if let Some(int_token) = int_token(name_ref) {
+        if int_token.text().chars().any(|c| !c.is_digit(10)) {
+            errors.push(SyntaxError::new(
+                "Tuple (struct) field access is only allowed through \
+                decimal integers with no underscores or suffix",
+                int_token.text_range(),
+            ));
+        }
+    }
+
+    fn int_token(name_ref: Option<ast::NameRef>) -> Option<SyntaxToken> {
+        name_ref?.syntax().first_child_or_token()?.into_token().filter(|it| it.kind() == INT_NUMBER)
+    }
+}
+
+fn validate_visibility(vis: ast::Visibility, errors: &mut Vec<SyntaxError>) {
+    let path_without_in_token = vis.in_token().is_none()
+        && vis.path().and_then(|p| p.as_single_name_ref()).and_then(|n| n.ident_token()).is_some();
+    if path_without_in_token {
+        errors.push(SyntaxError::new("incorrect visibility restriction", vis.syntax.text_range()));
+    }
+    let parent = match vis.syntax().parent() {
+        Some(it) => it,
+        None => return,
+    };
+    match parent.kind() {
+        FN | CONST | TYPE_ALIAS => (),
+        _ => return,
+    }
+
+    let impl_def = match parent.parent().and_then(|it| it.parent()).and_then(ast::Impl::cast) {
+        Some(it) => it,
+        None => return,
+    };
+    // FIXME: disable validation if there's an attribute, since some proc macros use this syntax.
+    // ideally the validation would run only on the fully expanded code, then this wouldn't be necessary.
+    if impl_def.trait_().is_some() && impl_def.attrs().next().is_none() {
+        errors.push(SyntaxError::new("Unnecessary visibility qualifier", vis.syntax.text_range()));
+    }
+}
+
+fn validate_range_expr(expr: ast::RangeExpr, errors: &mut Vec<SyntaxError>) {
+    if expr.op_kind() == Some(ast::RangeOp::Inclusive) && expr.end().is_none() {
+        errors.push(SyntaxError::new(
+            "An inclusive range must have an end expression",
+            expr.syntax().text_range(),
+        ));
+    }
+}
+
+fn validate_path_keywords(segment: ast::PathSegment, errors: &mut Vec<SyntaxError>) {
+    let path = segment.parent_path();
+    let is_path_start = segment.coloncolon_token().is_none() && path.qualifier().is_none();
+
+    if let Some(token) = segment.self_token() {
+        if !is_path_start {
+            errors.push(SyntaxError::new(
+                "The `self` keyword is only allowed as the first segment of a path",
+                token.text_range(),
+            ));
+        }
+    } else if let Some(token) = segment.crate_token() {
+        if !is_path_start || use_prefix(path).is_some() {
+            errors.push(SyntaxError::new(
+                "The `crate` keyword is only allowed as the first segment of a path",
+                token.text_range(),
+            ));
+        }
+    }
+
+    fn use_prefix(mut path: ast::Path) -> Option<ast::Path> {
+        for node in path.syntax().ancestors().skip(1) {
+            match_ast! {
+                match node {
+                    ast::UseTree(it) => if let Some(tree_path) = it.path() {
+                        // Even a top-level path exists within a `UseTree` so we must explicitly
+                        // allow our path but disallow anything else
+                        if tree_path != path {
+                            return Some(tree_path);
+                        }
+                    },
+                    ast::UseTreeList(_) => continue,
+                    ast::Path(parent) => path = parent,
+                    _ => return None,
+                }
+            };
+        }
+        None
+    }
+}
+
+fn validate_trait_object_ref_ty(ty: ast::RefType, errors: &mut Vec<SyntaxError>) {
+    if let Some(ast::Type::DynTraitType(ty)) = ty.ty() {
+        if let Some(err) = validate_trait_object_ty(ty) {
+            errors.push(err);
+        }
+    }
+}
+
+fn validate_trait_object_ptr_ty(ty: ast::PtrType, errors: &mut Vec<SyntaxError>) {
+    if let Some(ast::Type::DynTraitType(ty)) = ty.ty() {
+        if let Some(err) = validate_trait_object_ty(ty) {
+            errors.push(err);
+        }
+    }
+}
+
+fn validate_trait_object_fn_ptr_ret_ty(ty: ast::FnPtrType, errors: &mut Vec<SyntaxError>) {
+    if let Some(ast::Type::DynTraitType(ty)) = ty.ret_type().and_then(|ty| ty.ty()) {
+        if let Some(err) = validate_trait_object_ty(ty) {
+            errors.push(err);
+        }
+    }
+}
+
+fn validate_trait_object_ty(ty: ast::DynTraitType) -> Option<SyntaxError> {
+    let tbl = ty.type_bound_list()?;
+
+    if tbl.bounds().count() > 1 {
+        let dyn_token = ty.dyn_token()?;
+        let potential_parenthesis =
+            algo::skip_trivia_token(dyn_token.prev_token()?, Direction::Prev)?;
+        let kind = potential_parenthesis.kind();
+        if !matches!(kind, T!['('] | T![<] | T![=]) {
+            return Some(SyntaxError::new("ambiguous `+` in a type", ty.syntax().text_range()));
+        }
+    }
+    None
+}
+
+fn validate_macro_rules(mac: ast::MacroRules, errors: &mut Vec<SyntaxError>) {
+    if let Some(vis) = mac.visibility() {
+        errors.push(SyntaxError::new(
+            "visibilities are not allowed on `macro_rules!` items",
+            vis.syntax().text_range(),
+        ));
+    }
+}
+
+fn validate_const(const_: ast::Const, errors: &mut Vec<SyntaxError>) {
+    if let Some(mut_token) = const_
+        .const_token()
+        .and_then(|t| t.next_token())
+        .and_then(|t| algo::skip_trivia_token(t, Direction::Next))
+        .filter(|t| t.kind() == T![mut])
+    {
+        errors.push(SyntaxError::new("const globals cannot be mutable", mut_token.text_range()));
+    }
+}
+
+fn validate_let_expr(let_: ast::LetExpr, errors: &mut Vec<SyntaxError>) {
+    let mut token = let_.syntax().clone();
+    loop {
+        token = match token.parent() {
+            Some(it) => it,
+            None => break,
+        };
+
+        if ast::ParenExpr::can_cast(token.kind()) {
+            continue;
+        } else if let Some(it) = ast::BinExpr::cast(token.clone()) {
+            if it.op_kind() == Some(ast::BinaryOp::LogicOp(ast::LogicOp::And)) {
+                continue;
+            }
+        } else if ast::IfExpr::can_cast(token.kind())
+            || ast::WhileExpr::can_cast(token.kind())
+            || ast::MatchGuard::can_cast(token.kind())
+        {
+            // It must be part of the condition since the expressions are inside a block.
+            return;
+        }
+
+        break;
+    }
+    errors.push(SyntaxError::new(
+        "`let` expressions are not supported here",
+        let_.syntax().text_range(),
+    ));
+}
diff --git a/src/tools/rust-analyzer/crates/syntax/src/validation/block.rs b/src/tools/rust-analyzer/crates/syntax/src/validation/block.rs
new file mode 100644
index 000000000..8eb4a10a3
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/syntax/src/validation/block.rs
@@ -0,0 +1,24 @@
+//! Logic for validating block expressions i.e. `ast::BlockExpr`.
+
+use crate::{
+    ast::{self, AstNode, HasAttrs},
+    SyntaxError,
+    SyntaxKind::*,
+};
+
+pub(crate) fn validate_block_expr(block: ast::BlockExpr, errors: &mut Vec<SyntaxError>) {
+    if let Some(parent) = block.syntax().parent() {
+        match parent.kind() {
+            FN | EXPR_STMT | STMT_LIST => return,
+            _ => {}
+        }
+    }
+    if let Some(stmt_list) = block.stmt_list() {
+        errors.extend(stmt_list.attrs().filter(|attr| attr.kind().is_inner()).map(|attr| {
+            SyntaxError::new(
+                "A block in this position cannot accept inner attributes",
+                attr.syntax().text_range(),
+            )
+        }));
+    }
+}