Applicability::MachineApplicable,
);
} else if ret_ty.is_closure() {
- // We're dealing with a closure, so we should suggest using `impl Fn` or trait bounds
- // to prevent the user from getting a papercut while trying to use the unique closure
- // syntax (e.g. `[closure@src/lib.rs:2:5: 2:9]`).
diag.help("consider using an `Fn`, `FnMut`, or `FnOnce` trait bound");
+ }
+ // Also note how `Fn` traits work just in case!
+ if ret_ty.is_closure() {
diag.note(
"for more information on `Fn` traits and closure types, see \
https://doc.rust-lang.org/book/ch13-01-closures.html",