Suggest removing `let` if `const let` is used

1 files changed, 10 insertions, 0 deletions

diff --git a/compiler/rustc_parse/src/parser/item.rs b/compiler/rustc_parse/src/parser/item.rs
index 2c1e5807aa7..1d92213be34 100644
--- a/compiler/rustc_parse/src/parser/item.rs
+++ b/compiler/rustc_parse/src/parser/item.rs
@@ -1124,6 +1124,16 @@ impl<'a> Parser<'a> {
                     Applicability::MaybeIncorrect,
                 )
                 .emit();
+        } else if self.eat_keyword(kw::Let) {
+            let span = self.prev_token.span;
+            self.struct_span_err(const_span.to(span), "`const` and `let` are mutually exclusive")
+                .span_suggestion(
+                    const_span.to(span),
+                    "remove `let`",
+                    "const",
+                    Applicability::MaybeIncorrect,
+                )
+                .emit();
         }
     }