tests/ui/type-alias-impl-trait/issue-58662-generator-with-lifetime.rs

   1 // check-pass
   2
   3 #![feature(generators, generator_trait)]
   4 #![feature(type_alias_impl_trait)]
   5
   6 use std::ops::{Generator, GeneratorState};
   7 use std::pin::Pin;
   8
   9 type RandGenerator<'a> = impl Generator<Return = (), Yield = u64> + 'a;
  10 fn rand_generator<'a>(rng: &'a ()) -> RandGenerator<'a> {
  11     move || {
  12         let _rng = rng;
  13         loop {
  14             yield 0;
  15         }
  16     }
  17 }
  18
  19 pub type RandGeneratorWithIndirection<'c> = impl Generator<Return = (), Yield = u64> + 'c;
  20 pub fn rand_generator_with_indirection<'a>(rng: &'a ()) -> RandGeneratorWithIndirection<'a> {
  21     fn helper<'b>(rng: &'b ()) -> impl 'b + Generator<Return = (), Yield = u64> {
  22         move || {
  23             let _rng = rng;
  24             loop {
  25                 yield 0;
  26             }
  27         }
  28     }
  29
  30     helper(rng)
  31 }
  32
  33 fn main() {
  34     let mut gen = rand_generator(&());
  35     match unsafe { Pin::new_unchecked(&mut gen) }.resume(()) {
  36         GeneratorState::Yielded(_) => {}
  37         GeneratorState::Complete(_) => {}
  38     };
  39 }