remove unused peekable

Author: matklad

src/libsyntax/ext/mbe/quoted.rs

@@ -10,7 +10,6 @@ use crate::tokenstream;
 use syntax_pos::Span;
 
 use rustc_data_structures::sync::Lrc;
-use std::iter::Peekable;
 
 /// Takes a `tokenstream::TokenStream` and returns a `Vec<self::TokenTree>`. Specifically, this
 /// takes a generic `TokenStream`, such as is used in the rest of the compiler, and returns a
@@ -43,7 +42,7 @@ pub(super) fn parse(
 
     // For each token tree in `input`, parse the token into a `self::TokenTree`, consuming
     // additional trees if need be.
-    let mut trees = input.trees().peekable();
+    let mut trees = input.trees();
     while let Some(tree) = trees.next() {
         // Given the parsed tree, if there is a metavar and we are expecting matchers, actually
         // parse out the matcher (i.e., in `$id:ident` this would parse the `:` and `ident`).
@@ -99,7 +98,7 @@ pub(super) fn parse(
 ///   unstable features or not.
 fn parse_tree(
     tree: tokenstream::TokenTree,
-    trees: &mut Peekable<impl Iterator<Item = tokenstream::TokenTree>>,
+    trees: &mut impl Iterator<Item = tokenstream::TokenTree>,
     expect_matchers: bool,
     sess: &ParseSess,
 ) -> TokenTree {
@@ -222,7 +221,7 @@ fn parse_kleene_op(
 /// operator and separator, then a tuple with `(separator, KleeneOp)` is returned. Otherwise, an
 /// error with the appropriate span is emitted to `sess` and a dummy value is returned.
 fn parse_sep_and_kleene_op(
-    input: &mut Peekable<impl Iterator<Item = tokenstream::TokenTree>>,
+    input: &mut impl Iterator<Item = tokenstream::TokenTree>,
     span: Span,
     sess: &ParseSess,
 ) -> (Option<Token>, KleeneToken) {