30 lines
459 B
Rust
30 lines
459 B
Rust
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// check-pass
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struct Foo<T, U>
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where
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(T, U): Trait,
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{
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f: <(T, U) as Trait>::Assoc,
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}
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trait Trait {
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type Assoc: ?Sized;
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}
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struct Count<const N: usize>;
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impl<const N: usize> Trait for (i32, Count<N>) {
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type Assoc = [(); N];
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}
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impl<'a> Trait for (u32, ()) {
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type Assoc = [()];
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}
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// Test that we can unsize several trait params in creative ways.
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fn unsize<const N: usize>(x: &Foo<i32, Count<N>>) -> &Foo<u32, ()> {
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x
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}
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fn main() {}
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