29 lines
548 B
Rust
29 lines
548 B
Rust
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// Test that specializing on opaque types is allowed
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#![feature(min_specialization, type_alias_impl_trait)]
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trait SpecTrait<U, V> {
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fn f();
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}
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impl<U> SpecTrait<U, ()> for () {
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default fn f() {}
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}
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type Opaque = impl Tuple;
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trait Tuple {}
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impl Tuple for () {}
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// FIXME: this passes if we use `<(), ()>` here instead of `<(), Opaque>`,
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// even though there can't be more overlap from the opaque version
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impl SpecTrait<(), Opaque> for () {
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//~^ ERROR: conflicting implementations
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fn f() {}
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}
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fn foo() -> Opaque {}
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fn main() {}
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