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// WF check for impl Trait in associated type position.
//
//@ revisions: pass pass_next fail
//@ [pass] check-pass
//@ [pass_next] compile-flags: -Znext-solver
//@ [pass_next] check-pass
//@ [fail] check-fail
#![feature(impl_trait_in_assoc_type)]
// The hidden type here (`&'a T`) requires proving `T: 'a`.
// We know it holds because of implied bounds from the impl header.
#[cfg(any(pass, pass_next))]
mod pass {
trait Trait<Req> {
type Opaque1;
fn constrain_opaque1(req: Req) -> Self::Opaque1;
}
impl<'a, T> Trait<&'a T> for () {
type Opaque1 = impl IntoIterator<Item = impl Sized + 'a>;
fn constrain_opaque1(req: &'a T) -> Self::Opaque1 {
[req]
}
}
}
// The hidden type here (`&'a T`) requires proving `T: 'a`,
// but that is not known to hold in the impl.
#[cfg(fail)]
mod fail {
trait Trait<'a, T> {
type Opaque;
fn constrain_opaque(req: &'a T) -> Self::Opaque;
}
impl<'a, T> Trait<'a, T> for () {
type Opaque = impl Sized + 'a;
fn constrain_opaque(req: &'a T) -> Self::Opaque {
req
//[fail]~^ ERROR the parameter type `T` may not live long enough
//[fail]~| ERROR the parameter type `T` may not live long enough
}
}
}
fn main() {}
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