34 lines
890 B
Rust
34 lines
890 B
Rust
// Copyright 2012 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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trait TraitA {
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fn method_a(&self) -> int;
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}
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trait TraitB {
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fn gimme_an_a<A:TraitA>(&self, a: A) -> int;
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}
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impl TraitB for int {
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fn gimme_an_a<A:TraitA>(&self, a: A) -> int {
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a.method_a() + *self
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}
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}
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fn call_it<B:TraitB>(b: B) -> int {
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let y = 4u;
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b.gimme_an_a(y) //~ ERROR failed to find an implementation of trait TraitA
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}
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fn main() {
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let x = 3i;
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assert_eq!(call_it(x), 22);
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}
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