32 lines
989 B
Rust
32 lines
989 B
Rust
// Copyright 2015 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 Factory {
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type Product;
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fn create(&self) -> <Self as Factory>::Product;
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}
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impl Factory for f64 {
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type Product = f64;
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fn create(&self) -> f64 { *self * *self }
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}
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impl<A: Factory, B: Factory> Factory for (A, B) {
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type Product = (<A as Factory>::Product, <B as Factory>::Product);
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fn create(&self) -> (<A as Factory>::Product, <B as Factory>::Product) {
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let (ref a, ref b) = *self;
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(a.create(), b.create())
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}
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}
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fn main() {
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assert_eq!((16., 25.), (4., 5.).create());
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}
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