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// The WF requirements of the *unnormalized* form of type annotations
// can guide inference.
//@ check-pass
pub trait EqualTo {
type Ty;
}
impl<X> EqualTo for X {
type Ty = X;
}
trait MyTrait<U: EqualTo<Ty = Self>> {
type Out;
}
impl<T, U: EqualTo<Ty = T>> MyTrait<U> for T {
type Out = ();
}
fn main() {
let _: <_ as MyTrait<u8>>::Out;
// We shoud be able to infer a value for the inference variable above.
// The WF of the unnormalized projection requires `u8: EqualTo<Ty = _>`,
// which is sufficient to guide inference.
}
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