diff options
| -rw-r--r-- | compiler/rustc_expand/src/mbe/macro_rules.rs | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/compiler/rustc_expand/src/mbe/macro_rules.rs b/compiler/rustc_expand/src/mbe/macro_rules.rs index 9ed4c56efb3..d4504ba720e 100644 --- a/compiler/rustc_expand/src/mbe/macro_rules.rs +++ b/compiler/rustc_expand/src/mbe/macro_rules.rs @@ -894,12 +894,12 @@ fn check_redundant_vis_repetition( seq: &SequenceRepetition, span: &DelimSpan, ) { - let is_zero_or_one: bool = seq.kleene.op == KleeneOp::ZeroOrOne; - let is_vis = seq.tts.first().map_or(false, |tt| { - matches!(tt, mbe::TokenTree::MetaVarDecl { kind: NonterminalKind::Vis, .. }) - }); - - if is_vis && is_zero_or_one { + if seq.kleene.op == KleeneOp::ZeroOrOne + && matches!( + seq.tts.first(), + Some(mbe::TokenTree::MetaVarDecl { kind: NonterminalKind::Vis, .. }) + ) + { err.note("a `vis` fragment can already be empty"); err.multipart_suggestion( "remove the `$(` and `)?`", |