bba701c59d
This completes the last stage of the renaming of the comparison hierarchy of traits. This change renames TotalEq to Eq and TotalOrd to Ord. In the future the new Eq/Ord will be filled out with their appropriate methods, but for now this change is purely a renaming change. [breaking-change]
44 lines
1.2 KiB
Rust
44 lines
1.2 KiB
Rust
// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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// check that the derived impls for the comparison traits shortcircuit
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// where possible, by having a type that fails when compared as the
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// second element, so this passes iff the instances shortcircuit.
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pub struct FailCmp;
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impl PartialEq for FailCmp {
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fn eq(&self, _: &FailCmp) -> bool { fail!("eq") }
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}
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impl PartialOrd for FailCmp {
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fn lt(&self, _: &FailCmp) -> bool { fail!("lt") }
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}
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impl Eq for FailCmp {}
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impl Ord for FailCmp {
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fn cmp(&self, _: &FailCmp) -> Ordering { fail!("cmp") }
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}
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#[deriving(PartialEq,PartialOrd,Eq,Ord)]
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struct ShortCircuit {
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x: int,
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y: FailCmp
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}
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pub fn main() {
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let a = ShortCircuit { x: 1, y: FailCmp };
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let b = ShortCircuit { x: 2, y: FailCmp };
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assert!(a != b);
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assert!(a < b);
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assert_eq!(a.cmp(&b), ::std::cmp::Less);
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}
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