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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /third_party/rust/quote/src/ext.rs
parentInitial commit. (diff)
downloadfirefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz
firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esr
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/quote/src/ext.rs')
-rw-r--r--third_party/rust/quote/src/ext.rs110
1 files changed, 110 insertions, 0 deletions
diff --git a/third_party/rust/quote/src/ext.rs b/third_party/rust/quote/src/ext.rs
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+++ b/third_party/rust/quote/src/ext.rs
@@ -0,0 +1,110 @@
+use super::ToTokens;
+use core::iter;
+use proc_macro2::{TokenStream, TokenTree};
+
+/// TokenStream extension trait with methods for appending tokens.
+///
+/// This trait is sealed and cannot be implemented outside of the `quote` crate.
+pub trait TokenStreamExt: private::Sealed {
+ /// For use by `ToTokens` implementations.
+ ///
+ /// Appends the token specified to this list of tokens.
+ fn append<U>(&mut self, token: U)
+ where
+ U: Into<TokenTree>;
+
+ /// For use by `ToTokens` implementations.
+ ///
+ /// ```
+ /// # use quote::{quote, TokenStreamExt, ToTokens};
+ /// # use proc_macro2::TokenStream;
+ /// #
+ /// struct X;
+ ///
+ /// impl ToTokens for X {
+ /// fn to_tokens(&self, tokens: &mut TokenStream) {
+ /// tokens.append_all(&[true, false]);
+ /// }
+ /// }
+ ///
+ /// let tokens = quote!(#X);
+ /// assert_eq!(tokens.to_string(), "true false");
+ /// ```
+ fn append_all<I>(&mut self, iter: I)
+ where
+ I: IntoIterator,
+ I::Item: ToTokens;
+
+ /// For use by `ToTokens` implementations.
+ ///
+ /// Appends all of the items in the iterator `I`, separated by the tokens
+ /// `U`.
+ fn append_separated<I, U>(&mut self, iter: I, op: U)
+ where
+ I: IntoIterator,
+ I::Item: ToTokens,
+ U: ToTokens;
+
+ /// For use by `ToTokens` implementations.
+ ///
+ /// Appends all tokens in the iterator `I`, appending `U` after each
+ /// element, including after the last element of the iterator.
+ fn append_terminated<I, U>(&mut self, iter: I, term: U)
+ where
+ I: IntoIterator,
+ I::Item: ToTokens,
+ U: ToTokens;
+}
+
+impl TokenStreamExt for TokenStream {
+ fn append<U>(&mut self, token: U)
+ where
+ U: Into<TokenTree>,
+ {
+ self.extend(iter::once(token.into()));
+ }
+
+ fn append_all<I>(&mut self, iter: I)
+ where
+ I: IntoIterator,
+ I::Item: ToTokens,
+ {
+ for token in iter {
+ token.to_tokens(self);
+ }
+ }
+
+ fn append_separated<I, U>(&mut self, iter: I, op: U)
+ where
+ I: IntoIterator,
+ I::Item: ToTokens,
+ U: ToTokens,
+ {
+ for (i, token) in iter.into_iter().enumerate() {
+ if i > 0 {
+ op.to_tokens(self);
+ }
+ token.to_tokens(self);
+ }
+ }
+
+ fn append_terminated<I, U>(&mut self, iter: I, term: U)
+ where
+ I: IntoIterator,
+ I::Item: ToTokens,
+ U: ToTokens,
+ {
+ for token in iter {
+ token.to_tokens(self);
+ term.to_tokens(self);
+ }
+ }
+}
+
+mod private {
+ use proc_macro2::TokenStream;
+
+ pub trait Sealed {}
+
+ impl Sealed for TokenStream {}
+}