rust/src/test/run-pass/traits.rs

57 lines
1.4 KiB
Rust

// Copyright 2012 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.
//xfail-test
// Sketching traits.
// methods with no implementation are required; methods with an
// implementation are provided. No "req" keyword necessary.
trait Eq {
fn eq(a: self) -> bool;
fn neq(a: self) -> bool {
!self.eq(a)
}
}
// The `<` is pronounced `extends`. Also under consideration is `<:`.
// Just using `:` is frowned upon, because (paraphrasing dherman) `:`
// is supposed to separate things from different universes.
trait Ord < Eq {
fn lt(a: self) -> bool;
fn lte(a: self) -> bool {
self.lt(a) || self.eq(a)
}
fn gt(a: self) -> bool {
!self.lt(a) && !self.eq(a)
}
fn gte(a: self) -> bool {
!self.lt(a)
}
}
// pronounced "impl of Ord for int" -- not sold on this yet
impl Ord for int {
fn lt(a: &int) -> bool {
self < (*a)
}
// is this the place to put this?
fn eq(a: &int) -> bool {
self == (*a)
}
}