1 files changed, 31 insertions, 0 deletions
diff --git a/compiler/rustc_middle/src/hir/nested_filter.rs b/compiler/rustc_middle/src/hir/nested_filter.rs
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+++ b/compiler/rustc_middle/src/hir/nested_filter.rs
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+use rustc_hir::intravisit::nested_filter::NestedFilter;
+
+/// Do not visit nested item-like things, but visit nested things
+/// that are inside of an item-like.
+///
+/// Notably, possible occurrences of bodies in non-item-like things
+/// include: closures/generators, inline `const {}` blocks, and
+/// constant arguments of types, e.g. in `let _: [(); /* HERE */];`.
+///
+/// **This is the most common choice.** A very common pattern is
+/// to use `visit_all_item_likes_in_crate()` as an outer loop,
+/// and to have the visitor that visits the contents of each item
+/// using this setting.
+pub struct OnlyBodies(());
+impl<'hir> NestedFilter<'hir> for OnlyBodies {
+    type Map = crate::hir::map::Map<'hir>;
+    const INTER: bool = false;
+    const INTRA: bool = true;
+}
+
+/// Visits all nested things, including item-likes.
+///
+/// **This is an unusual choice.** It is used when you want to
+/// process everything within their lexical context. Typically you
+/// kick off the visit by doing `walk_krate()`.
+pub struct All(());
+impl<'hir> NestedFilter<'hir> for All {
+    type Map = crate::hir::map::Map<'hir>;
+    const INTER: bool = true;
+    const INTRA: bool = true;
+}