31 lines
735 B
Rust
31 lines
735 B
Rust
//@ revisions: current next
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//@ ignore-compare-mode-next-solver (explicit revisions)
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//@[next] compile-flags: -Znext-solver
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//@ check-pass
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#![allow(warnings)]
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trait Trait<U> {
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type Assoc;
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}
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impl<T> Trait<u64> for T {
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type Assoc = T;
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}
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fn lazy_init<T: Trait<U>, U>() -> (T, <T as Trait<U>>::Assoc) {
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todo!()
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}
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fn foo<T: Trait<u32, Assoc = T>>(x: T) {
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// When considering impl candidates to be equally valid as env candidates
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// this ends up being ambiguous as `U` can be both `u32´ and `u64` here.
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//
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// This is acceptable breakage but we should still note that it's
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// theoretically breaking.
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let (delayed, mut proj) = lazy_init::<_, _>();
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proj = x;
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let _: T = delayed;
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}
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fn main() {}
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