31 lines
607 B
Rust
31 lines
607 B
Rust
// compile-flags: -Ztrait-solver=next
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#![feature(specialization)]
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//~^ WARN the feature `specialization` is incomplete
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trait Default {
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type Id;
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fn intu(&self) -> &Self::Id;
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}
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impl<T> Default for T {
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default type Id = T;
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fn intu(&self) -> &Self::Id {
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self
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//~^ ERROR cannot satisfy `T <: <T as Default>::Id`
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}
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}
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fn transmute<T: Default<Id = U>, U: Copy>(t: T) -> U {
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*t.intu()
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}
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use std::num::NonZeroU8;
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fn main() {
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let s = transmute::<u8, Option<NonZeroU8>>(0);
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//~^ ERROR cannot satisfy `<u8 as Default>::Id == Option<NonZeroU8>
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assert_eq!(s, None);
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}
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