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			24 lines
		
	
	
		
			557 B
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			24 lines
		
	
	
		
			557 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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//@[next] check-pass
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#![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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        //[current]~^ 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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