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20 lines
403 B
Rust
20 lines
403 B
Rust
#![feature(type_alias_impl_trait)]
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type A = impl Foo;
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type B = impl Foo;
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trait Foo {}
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fn muh(x: A) -> B {
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if false {
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return x; // B's hidden type is A (opaquely)
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//~^ ERROR opaque type's hidden type cannot be another opaque type
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}
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Bar // A's hidden type is `Bar`, because all the return types are compared with each other
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}
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struct Bar;
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impl Foo for Bar {}
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fn main() {}
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