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 // revisions: min_tait full_tait
   6 #![feature(min_type_alias_impl_trait)]
   7 #![cfg_attr(full_tait, feature(type_alias_impl_trait))]
   8 //[full_tait]~^ WARN incomplete
   9 #![feature(const_generics)]
  10 //~^ WARN the feature `const_generics` is incomplete
  11
  12 trait UnwrapItemsExt<'a, const C: usize> {
  13     type Iter;
  14     fn unwrap_items(self) -> Self::Iter;
  15 }
  16
  17 struct MyStruct<const C: usize> {}
  18
  19 trait MyTrait<'a, const C: usize> {
  20     type MyItem;
  21     const MY_CONST: usize;
  22 }
  23
  24 impl<'a, const C: usize> MyTrait<'a, C> for MyStruct<C> {
  25     type MyItem = u8;
  26     const MY_CONST: usize = C;
  27 }
  28
  29 impl<'a, I, const C: usize> UnwrapItemsExt<'a, C> for I {
  30     type Iter = impl MyTrait<'a, C>;
  31
  32     fn unwrap_items(self) -> Self::Iter {
  33         MyStruct::<C> {}
  34     }
  35 }
  36
  37 fn main() {}