25 lines
393 B
Rust
25 lines
393 B
Rust
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#![feature(return_position_impl_trait_in_trait)]
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#![allow(incomplete_features)]
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use std::fmt::Display;
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use std::ops::Deref;
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trait Foo {
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fn bar(self) -> impl Deref<Target = impl Display + ?Sized>;
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}
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struct A;
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impl Foo for A {
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fn bar(self) -> &'static str {
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"Hello, world"
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}
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}
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fn foo<T: Foo>(t: T) {
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let () = t.bar();
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//~^ ERROR mismatched types
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}
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fn main() {}
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