34 lines
488 B
Rust
34 lines
488 B
Rust
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#![feature(trait_upcasting)]
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#![feature(trait_alias)]
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// Although we *elaborate* `T: Alias` to `i32: B`, we should
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// not consider `B` to be a supertrait of the type.
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trait Alias = A where i32: B;
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trait A {}
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trait B {
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fn test(&self);
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}
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trait C: Alias {}
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impl A for () {}
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impl C for () {}
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impl B for i32 {
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fn test(&self) {
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println!("hi {self}");
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}
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}
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fn test(x: &dyn C) -> &dyn B {
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x
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//~^ ERROR mismatched types
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}
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fn main() {
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let x: &dyn C = &();
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}
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