mirror of https://github.com/rust-lang/rust
42 lines
1.6 KiB
Plaintext
42 lines
1.6 KiB
Plaintext
error[E0525]: expected a closure that implements the `async Fn` trait, but this closure only implements `async FnOnce`
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--> $DIR/wrong-fn-kind.rs:17:20
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LL | needs_async_fn(move || async move {
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| -------------- -^^^^^^
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| | |
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| _____|______________this closure implements `async FnOnce`, not `async Fn`
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| | |
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| | required by a bound introduced by this call
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LL | |
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LL | | println!("{x}");
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| | - closure is `async FnOnce` because it moves the variable `x` out of its environment
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LL | | });
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| |_____- the requirement to implement `async Fn` derives from here
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note: required by a bound in `needs_async_fn`
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--> $DIR/wrong-fn-kind.rs:5:27
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LL | fn needs_async_fn(_: impl async Fn()) {}
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| ^^^^^^^^^^ required by this bound in `needs_async_fn`
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error[E0596]: cannot borrow `x` as mutable, as it is a captured variable in a `Fn` closure
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--> $DIR/wrong-fn-kind.rs:9:20
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LL | fn needs_async_fn(_: impl async Fn()) {}
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| --------------- change this to accept `FnMut` instead of `Fn`
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...
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LL | needs_async_fn(async || {
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| -------------- ^^^^^^^^
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| | |
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| | cannot borrow as mutable
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| | in this closure
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| expects `Fn` instead of `FnMut`
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LL |
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LL | x += 1;
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| - mutable borrow occurs due to use of `x` in closure
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error: aborting due to 2 previous errors
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Some errors have detailed explanations: E0525, E0596.
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For more information about an error, try `rustc --explain E0525`.
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