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diff --git a/rust/vendor/syn-0.15.44/src/parse_quote.rs b/rust/vendor/syn-0.15.44/src/parse_quote.rs
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+/// Quasi-quotation macro that accepts input like the [`quote!`] macro but uses
+/// type inference to figure out a return type for those tokens.
+///
+/// [`quote!`]: https://docs.rs/quote/0.6/quote/index.html
+///
+/// The return type can be any syntax tree node that implements the [`Parse`]
+/// trait.
+///
+/// [`Parse`]: parse::Parse
+///
+/// ```edition2018
+/// use quote::quote;
+/// use syn::{parse_quote, Stmt};
+///
+/// fn main() {
+///     let name = quote!(v);
+///     let ty = quote!(u8);
+///
+///     let stmt: Stmt = parse_quote! {
+///         let #name: #ty = Default::default();
+///     };
+///
+///     println!("{:#?}", stmt);
+/// }
+/// ```
+///
+/// *This macro is available if Syn is built with the `"parsing"` feature,
+/// although interpolation of syntax tree nodes into the quoted tokens is only
+/// supported if Syn is built with the `"printing"` feature as well.*
+///
+/// # Example
+///
+/// The following helper function adds a bound `T: HeapSize` to every type
+/// parameter `T` in the input generics.
+///
+/// ```edition2018
+/// use syn::{parse_quote, Generics, GenericParam};
+///
+/// // Add a bound `T: HeapSize` to every type parameter T.
+/// fn add_trait_bounds(mut generics: Generics) -> Generics {
+///     for param in &mut generics.params {
+///         if let GenericParam::Type(type_param) = param {
+///             type_param.bounds.push(parse_quote!(HeapSize));
+///         }
+///     }
+///     generics
+/// }
+/// ```
+///
+/// # Special cases
+///
+/// This macro can parse the following additional types as a special case even
+/// though they do not implement the `Parse` trait.
+///
+/// - [`Attribute`] — parses one attribute, allowing either outer like `#[...]`
+///   or inner like `#![...]`
+/// - [`Punctuated<T, P>`] — parses zero or more `T` separated by punctuation
+///   `P` with optional trailing punctuation
+///
+/// [`Punctuated<T, P>`]: punctuated::Punctuated
+///
+/// # Panics
+///
+/// Panics if the tokens fail to parse as the expected syntax tree type. The
+/// caller is responsible for ensuring that the input tokens are syntactically
+/// valid.
+//
+// TODO: allow Punctuated to be inferred as intra doc link, currently blocked on
+// https://github.com/rust-lang/rust/issues/62834
+#[macro_export(local_inner_macros)]
+macro_rules! parse_quote {
+    ($($tt:tt)*) => {
+        $crate::parse_quote::parse($crate::export::From::from(quote_impl!($($tt)*)))
+    };
+}
+
+#[cfg(not(syn_can_call_macro_by_path))]
+#[doc(hidden)]
+#[macro_export]
+macro_rules! quote_impl {
+    ($($tt:tt)*) => {
+        // Require caller to have their own `#[macro_use] extern crate quote`.
+        quote!($($tt)*)
+    };
+}
+
+#[cfg(syn_can_call_macro_by_path)]
+#[doc(hidden)]
+#[macro_export]
+macro_rules! quote_impl {
+    ($($tt:tt)*) => {
+        $crate::export::quote::quote!($($tt)*)
+    };
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// Can parse any type that implements Parse.
+
+use parse::{Parse, ParseStream, Parser, Result};
+use proc_macro2::TokenStream;
+
+// Not public API.
+#[doc(hidden)]
+pub fn parse<T: ParseQuote>(token_stream: TokenStream) -> T {
+    let parser = T::parse;
+    match parser.parse2(token_stream) {
+        Ok(t) => t,
+        Err(err) => panic!("{}", err),
+    }
+}
+
+// Not public API.
+#[doc(hidden)]
+pub trait ParseQuote: Sized {
+    fn parse(input: ParseStream) -> Result<Self>;
+}
+
+impl<T: Parse> ParseQuote for T {
+    fn parse(input: ParseStream) -> Result<Self> {
+        <T as Parse>::parse(input)
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// Any other types that we want `parse_quote!` to be able to parse.
+
+use punctuated::Punctuated;
+#[cfg(any(feature = "full", feature = "derive"))]
+use {attr, Attribute};
+
+#[cfg(any(feature = "full", feature = "derive"))]
+impl ParseQuote for Attribute {
+    fn parse(input: ParseStream) -> Result<Self> {
+        if input.peek(Token![#]) && input.peek2(Token![!]) {
+            attr::parsing::single_parse_inner(input)
+        } else {
+            attr::parsing::single_parse_outer(input)
+        }
+    }
+}
+
+impl<T: Parse, P: Parse> ParseQuote for Punctuated<T, P> {
+    fn parse(input: ParseStream) -> Result<Self> {
+        Self::parse_terminated(input)
+    }
+}