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//@ run-pass
trait Factory {
type Product;
fn create(&self) -> <Self as Factory>::Product;
}
impl Factory for f64 {
type Product = f64;
fn create(&self) -> f64 { *self * *self }
}
impl<A: Factory, B: Factory> Factory for (A, B) {
type Product = (<A as Factory>::Product, <B as Factory>::Product);
fn create(&self) -> (<A as Factory>::Product, <B as Factory>::Product) {
let (ref a, ref b) = *self;
(a.create(), b.create())
}
}
fn main() {
assert_eq!((16., 25.), (4., 5.).create());
}
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