34 lines
645 B
Rust
34 lines
645 B
Rust
// 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.
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#![feature(specialization)] //~ WARN the feature `specialization` is incomplete
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use std::convert::Into;
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trait Trait {
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fn to_u8(&self) -> u8;
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}
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trait WithAssoc {
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type Item;
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fn to_item(&self) -> Self::Item;
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}
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impl<T, U> Trait for T where T: WithAssoc<Item=U>, U: Into<u8> {
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fn to_u8(&self) -> u8 {
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self.to_item().into()
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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 to_item(&self) -> u8 { *self }
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}
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impl Trait for u8 {}
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fn main() {
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assert!(3u8.to_u8() == 3u8);
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}
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