[rustc.git] / src / test / ui / specialization / defaultimpl / overlap-projection.rs

// run-pass

// Test that impls on projected self types can resolve overlap, even when the
// projections involve specialization, so long as the associated type is
// provided by the most specialized impl.

#![feature(specialization)] //~ WARN the feature `specialization` is incomplete

trait Assoc {
    type Output;
}

default impl<T> Assoc for T {
    type Output = bool;
}

impl Assoc for u8 { type Output = u8; }
impl Assoc for u16 { type Output = u16; }

trait Foo {}
impl Foo for u32 {}
impl Foo for <u8 as Assoc>::Output {}
impl Foo for <u16 as Assoc>::Output {}

fn main() {}
Commit	Line	Data
b7449926 XL	1	// run-pass
b7449926 XL	2
7cac9316 XL	3	// Test that impls on projected self types can resolve overlap, even when the
	4	// projections involve specialization, so long as the associated type is
	5	// provided by the most specialized impl.
	6
f035d41b	7	#![feature(specialization)] //~ WARN the feature `specialization` is incomplete
7cac9316 XL	8
	9	trait Assoc {
	10	type Output;
	11	}
	12
	13	default impl<T> Assoc for T {
	14	type Output = bool;
	15	}
	16
	17	impl Assoc for u8 { type Output = u8; }
	18	impl Assoc for u16 { type Output = u16; }
	19
	20	trait Foo {}
	21	impl Foo for u32 {}
	22	impl Foo for <u8 as Assoc>::Output {}
	23	impl Foo for <u16 as Assoc>::Output {}
	24
	25	fn main() {}