error[E0525]: expected a closure that implements the `Fn` trait, but this closure only implements `FnOnce` --> $DIR/closure-origin-tuple-diagnostics.rs:9:13 | LL | let c = || { | ^^ this closure implements `FnOnce`, not `Fn` LL | let s = s.1; | --- closure is `FnOnce` because it moves the variable `s.1` out of its environment LL | }; LL | expect_fn(c); | --------- - the requirement to implement `Fn` derives from here | | | required by a bound introduced by this call | note: required by a bound in `expect_fn` --> $DIR/closure-origin-tuple-diagnostics.rs:5:17 | LL | fn expect_fn(_f: F) {} | ^^^^ required by this bound in `expect_fn` error: aborting due to previous error For more information about this error, try `rustc --explain E0525`.