Add another test using projection types in impls.

This commit is contained in:
Niko Matsakis 2015-01-08 12:02:34 -05:00
parent 0d9a11d6ad
commit cc1776ef1e

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// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// Test where the impl self type uses a projection from a constant type.
trait Int
{
type T;
}
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));
}