26 lines
684 B
Rust
26 lines
684 B
Rust
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// edition:2021
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// RPITIT is not enough to allow use of async functions
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#![allow(incomplete_features)]
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#![feature(return_position_impl_trait_in_trait)]
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trait T {
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async fn foo(); //~ ERROR functions in traits cannot be declared `async`
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}
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// Both return_position_impl_trait_in_trait and async_fn_in_trait are required for this (see also
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// feature-gate-return_position_impl_trait_in_trait.rs)
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trait T2 {
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async fn foo() -> impl Sized; //~ ERROR functions in traits cannot be declared `async`
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}
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trait T3 {
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fn foo() -> impl std::future::Future<Output = ()>;
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}
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impl T3 for () {
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async fn foo() {} //~ ERROR functions in traits cannot be declared `async`
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}
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fn main() {}
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