mirror of https://github.com/rust-lang/rust
44 lines
1.3 KiB
Rust
44 lines
1.3 KiB
Rust
//@ run-rustfix
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//
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#![allow(warnings)]
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struct Wrapper<'a, T: ?Sized>(&'a T);
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trait Project {
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type Projected<'a> where Self: 'a;
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fn project(this: Wrapper<'_, Self>) -> Self::Projected<'_>;
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}
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trait MyTrait {}
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trait ProjectedMyTrait {}
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impl<T> Project for Option<T> {
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type Projected<'a> = Option<Wrapper<'a, T>> where T: 'a;
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fn project(this: Wrapper<'_, Self>) -> Self::Projected<'_> {
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this.0.as_ref().map(Wrapper)
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}
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}
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impl<T: MyTrait> MyTrait for Option<Wrapper<'_, T>> {}
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impl<T: ProjectedMyTrait> MyTrait for Wrapper<'_, T> {}
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impl<T> ProjectedMyTrait for T
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where
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T: Project,
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for<'a> T::Projected<'a>: MyTrait,
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//~^ NOTE due to current limitations in the borrow checker, this implies a `'static` lifetime
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//~| NOTE due to current limitations in the borrow checker, this implies a `'static` lifetime
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{}
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fn require_trait<T: MyTrait>(_: T) {}
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fn foo<T : MyTrait + 'static + 'static, U : MyTrait + 'static + 'static>(wrap: Wrapper<'_, Option<T>>, wrap1: Wrapper<'_, Option<U>>) {
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//~^ HELP consider restricting the type parameter to the `'static` lifetime
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//~| HELP consider restricting the type parameter to the `'static` lifetime
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require_trait(wrap);
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//~^ ERROR `T` does not live long enough
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require_trait(wrap1);
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//~^ ERROR `U` does not live long enough
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}
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fn main() {}
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