mirror of https://github.com/rust-lang/rust
48 lines
789 B
Rust
48 lines
789 B
Rust
//@ edition:2018
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// See issue 60414
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// Reduction to `impl Trait`
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struct Foo<T>(T);
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trait FooLike {
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type Output;
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}
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impl<T> FooLike for Foo<T> {
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type Output = T;
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}
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mod impl_trait {
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use super::*;
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trait Trait {
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type Assoc;
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}
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/// `T::Assoc` can't be normalized any further here.
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fn foo_fail<T: Trait>() -> impl FooLike<Output = T::Assoc> {
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//~^ ERROR: type mismatch
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Foo(())
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}
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}
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// Same with lifetimes in the trait
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mod lifetimes {
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use super::*;
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trait Trait<'a> {
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type Assoc;
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}
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/// Missing bound constraining `Assoc`, `T::Assoc` can't be normalized further.
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fn foo2_fail<'a, T: Trait<'a>>() -> impl FooLike<Output = T::Assoc> {
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//~^ ERROR: type mismatch
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Foo(())
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}
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}
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fn main() {}
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