Rollup merge of rust-lang#91625 - est31:remove_indexes, r=oli-obk

Remove redundant [..]s

Author: matthiaskrgr

compiler/rustc_ast/src/util/literal.rs

@@ -57,7 +57,7 @@ impl LitKind {
                 // string in the token.
                 let s = symbol.as_str();
                 let symbol =
-                    if s.contains(&['\\', '\r'][..]) {
+                    if s.contains(&['\\', '\r']) {
                         let mut buf = String::with_capacity(s.len());
                         let mut error = Ok(());
                         unescape_literal(&s, Mode::Str, &mut |_, unescaped_char| {

compiler/rustc_ast_passes/src/feature_gate.rs

@@ -347,7 +347,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
 
                     if let Some(modifiers) = nested_meta.value_str() {
                         for modifier in modifiers.as_str().split(',') {
-                            if let Some(modifier) = modifier.strip_prefix(&['+', '-'][..]) {
+                            if let Some(modifier) = modifier.strip_prefix(&['+', '-']) {
                                 macro_rules! gate_modifier { ($($name:literal => $feature:ident)*) => {
                                     $(if modifier == $name {
                                         let msg = concat!("`#[link(modifiers=\"", $name, "\")]` is unstable");
@@ -383,7 +383,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
             }
 
             ast::ItemKind::Fn(..) => {
-                if self.sess.contains_name(&i.attrs[..], sym::start) {
+                if self.sess.contains_name(&i.attrs, sym::start) {
                     gate_feature_post!(
                         &self,
                         start,
@@ -396,7 +396,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
             }
 
             ast::ItemKind::Struct(..) => {
-                for attr in self.sess.filter_by_name(&i.attrs[..], sym::repr) {
+                for attr in self.sess.filter_by_name(&i.attrs, sym::repr) {
                     for item in attr.meta_item_list().unwrap_or_else(Vec::new) {
                         if item.has_name(sym::simd) {
                             gate_feature_post!(