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error[E0525]: expected a closure that implements the `AsyncFn` trait, but this closure only implements `AsyncFnOnce`
--> $DIR/wrong-fn-kind.rs:15:20
|
LL | needs_async_fn(move || async move {
| -------------- -^^^^^^
| | |
| _____|______________this closure implements `AsyncFnOnce`, not `AsyncFn`
| | |
| | required by a bound introduced by this call
LL | |
LL | | println!("{x}");
| | - closure is `AsyncFnOnce` because it moves the variable `x` out of its environment
LL | | });
| |_____- the requirement to implement `AsyncFn` derives from here
|
note: required by a bound in `needs_async_fn`
--> $DIR/wrong-fn-kind.rs:3:27
|
LL | fn needs_async_fn(_: impl AsyncFn()) {}
| ^^^^^^^^^ required by this bound in `needs_async_fn`
error[E0596]: cannot borrow `x` as mutable, as it is a captured variable in a `Fn` closure
--> $DIR/wrong-fn-kind.rs:7:20
|
LL | fn needs_async_fn(_: impl AsyncFn()) {}
| -------------- change this to accept `FnMut` instead of `Fn`
...
LL | needs_async_fn(async || {
| -------------- ^^^^^^^^
| | |
| | cannot borrow as mutable
| | in this closure
| expects `Fn` instead of `FnMut`
LL |
LL | x += 1;
| - mutable borrow occurs due to use of `x` in closure
error: aborting due to 2 previous errors
Some errors have detailed explanations: E0525, E0596.
For more information about an error, try `rustc --explain E0525`.
|
