associated-types-projection-from-known-type-in-impl.rs

//@ run-pass
// Test where the impl self type uses a projection from a constant type.


trait Int
{
    type T;

    fn dummy(&self) { } //~ WARN method `dummy` is never used
}

trait NonZero
{
    fn non_zero(self) -> bool;
}

impl Int for i32 { type T = i32; }
impl Int for i64 { type T = i64; }
impl Int for u32 { type T = u32; }
impl Int for u64 { type T = u64; }

impl NonZero for <i32 as Int>::T { fn non_zero(self) -> bool { self != 0 } }
impl NonZero for <i64 as Int>::T { fn non_zero(self) -> bool { self != 0 } }
impl NonZero for <u32 as Int>::T { fn non_zero(self) -> bool { self != 0 } }
impl NonZero for <u64 as Int>::T { fn non_zero(self) -> bool { self != 0 } }

fn main ()
{
    assert!(NonZero::non_zero(22_i32));
    assert!(NonZero::non_zero(22_i64));
    assert!(NonZero::non_zero(22_u32));
    assert!(NonZero::non_zero(22_u64));

    assert!(!NonZero::non_zero(0_i32));
    assert!(!NonZero::non_zero(0_i64));
    assert!(!NonZero::non_zero(0_u32));
    assert!(!NonZero::non_zero(0_u64));
}