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