46 lines
1.3 KiB
Rust
46 lines
1.3 KiB
Rust
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// 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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#[allow(default_methods)]
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trait Speak {
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fn say(&self, s:&str) -> ~str;
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fn hi(&self) -> ~str { hello(self) }
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}
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fn hello<S:Speak>(s:&S) -> ~str{
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s.say("hello")
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}
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impl Speak for int {
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fn say(&self, s:&str) -> ~str {
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fmt!("%s: %d", s, *self)
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}
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}
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impl<T: Speak> Speak for Option<T> {
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fn say(&self, s:&str) -> ~str {
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match *self {
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None => fmt!("%s - none", s),
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Some(ref x) => { ~"something!" + x.say(s) }
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}
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}
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}
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fn main() {
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assert_eq!(3.hi(), ~"hello: 3");
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assert_eq!(Some(Some(3)).hi(), ~"something!something!hello: 3");
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assert_eq!(None::<int>.hi(), ~"hello - none");
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// These fail because of a bug in monomorphization's ID generation.
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//assert_eq!(Some(None::<int>).hi(), ~"something!hello - none");
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//assert_eq!(Some(3).hi(), ~"something!hello: 3");
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}
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