src/test/ui/type-alias-impl-trait/issue-53678-generator-and-const-fn.rs

   1 #![feature(const_impl_trait, generators, generator_trait, rustc_attrs)]
   2 // revisions: min_tait full_tait
   3 #![feature(min_type_alias_impl_trait)]
   4 #![cfg_attr(full_tait, feature(impl_trait_in_bindings, type_alias_impl_trait))]
   5 //[full_tait]~^ WARN incomplete
   6 //[full_tait]~| WARN incomplete
   7
   8 use std::ops::Generator;
   9
  10 type GenOnce<Y, R> = impl Generator<Yield = Y, Return = R>;
  11
  12 const fn const_generator<Y, R>(yielding: Y, returning: R) -> GenOnce<Y, R> {
  13     move || {
  14         yield yielding;
  15
  16         return returning;
  17     }
  18 }
  19
  20 const FOO: GenOnce<usize, usize> = const_generator(10, 100); //[min_tait]~ ERROR not permitted here
  21
  22 #[rustc_error]
  23 fn main() {} //[full_tait]~ ERROR