2020-05-17 03:22:48 -05:00
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#![feature(specialization)] //~ WARN the feature `specialization` is incomplete
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2020-03-28 19:01:32 -05:00
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// check-pass
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trait Trait {
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type Assoc;
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}
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impl<T> Trait for T {
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default type Assoc = bool;
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}
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// This impl inherits the `Assoc` definition from above and "locks it in", or finalizes it, making
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// child impls unable to further specialize it. However, since the specialization graph didn't
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// correctly track this, we would refuse to project `Assoc` from this impl, even though that should
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// happen for items that are final.
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impl Trait for () {}
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fn foo<X: Trait<Assoc=bool>>() {}
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fn main() {
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foo::<()>(); // `<() as Trait>::Assoc` is normalized to `bool` correctly
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}
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