mirror of https://github.com/rust-lang/rust
23 lines
535 B
Rust
23 lines
535 B
Rust
//@ run-pass
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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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