tests/ui/type-alias-impl-trait/impl_trait_in_trait_defined_outside_trait2.rs

//! Check that we cannot instantiate a hidden type from another assoc type.

#![feature(impl_trait_in_assoc_type)]

trait Trait: Sized {
    type Assoc;
    type Foo;
    fn foo() -> Self::Assoc;
}

impl Trait for () {
    type Assoc = impl std::fmt::Debug;
    type Foo = [(); {
        let x: Self::Assoc = 42; //~ ERROR: mismatched types
        3
    }];
    fn foo() -> Self::Assoc {
        ""
    }
}

fn main() {}