mirror of https://github.com/rust-lang/rust.git
33 lines
690 B
Rust
33 lines
690 B
Rust
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// run-pass
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// Ensure that provided items are inherited properly even when impls vary in
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// type parameters *and* rely on projections, and the type parameters are input
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// types on the trait.
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#![feature(specialization)] //~ WARN the feature `specialization` is incomplete
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trait Trait<T> {
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fn convert(&self) -> T;
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}
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trait WithAssoc {
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type Item;
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fn as_item(&self) -> &Self::Item;
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}
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impl<T, U> Trait<U> for T where T: WithAssoc<Item=U>, U: Clone {
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fn convert(&self) -> U {
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self.as_item().clone()
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}
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}
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impl WithAssoc for u8 {
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type Item = u8;
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fn as_item(&self) -> &u8 { self }
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}
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impl Trait<u8> for u8 {}
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fn main() {
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assert!(3u8.convert() == 3u8);
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}
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