src/test/ui/type-alias-impl-trait/assoc-type-const.rs

   1 // Tests that we properly detect defining usages when using
   2 // const generics in an associated opaque type
   3 // check-pass
   4
   5 #![feature(type_alias_impl_trait)]
   6 #![feature(const_generics)]
   7 //~^ WARN the feature `const_generics` is incomplete and may cause the compiler to crash
   8
   9 trait UnwrapItemsExt<const C: usize> {
  10     type Iter;
  11     fn unwrap_items(self) -> Self::Iter;
  12 }
  13
  14 struct MyStruct<const C: usize> {}
  15
  16 trait MyTrait<'a, const C: usize> {
  17     type MyItem;
  18     const MY_CONST: usize;
  19 }
  20
  21 impl<'a, const C: usize> MyTrait<'a, {C}> for MyStruct<{C}> {
  22     type MyItem = u8;
  23     const MY_CONST: usize = C;
  24 }
  25
  26 impl<'a, I, const C: usize> UnwrapItemsExt<{C}> for I
  27 where
  28 {
  29     type Iter = impl MyTrait<'a, {C}>;
  30
  31     fn unwrap_items(self) -> Self::Iter {
  32         MyStruct::<{C}> {}
  33     }
  34 }
  35
  36 fn main() {}