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Diffstat (limited to '')
-rw-r--r-- | src/test/ui/type-alias-impl-trait/impl_trait_for_same_tait.rs | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/src/test/ui/type-alias-impl-trait/impl_trait_for_same_tait.rs b/src/test/ui/type-alias-impl-trait/impl_trait_for_same_tait.rs new file mode 100644 index 000000000..3f1a9d12b --- /dev/null +++ b/src/test/ui/type-alias-impl-trait/impl_trait_for_same_tait.rs @@ -0,0 +1,33 @@ +#![feature(type_alias_impl_trait)] + +trait Foo {} +impl Foo for () {} +impl Foo for i32 {} + +type Bar<T: Foo> = impl std::fmt::Debug; +fn defining_use<T: Foo>() -> Bar<T> { + 42 +} + +trait Bop {} + +impl Bop for Bar<()> {} + +// If the hidden type is the same, this is effectively a second impl for the same type. +impl Bop for Bar<i32> {} +//~^ ERROR conflicting implementations + +type Barr = impl std::fmt::Debug; +fn defining_use2() -> Barr { + 42 +} + +// Even completely different opaque types must conflict. +impl Bop for Barr {} +//~^ ERROR conflicting implementations + +// And obviously the hidden type must conflict, too. +impl Bop for i32 {} +//~^ ERROR conflicting implementations + +fn main() {} |