src/test/ui/type-alias-impl-trait/issue-60564.rs

   1 #![feature(type_alias_impl_trait)]
   2
   3 trait IterBits {
   4     type BitsIter: Iterator<Item = u8>;
   5     fn iter_bits(self, n: u8) -> Self::BitsIter;
   6 }
   7
   8 type IterBitsIter<T, E, I> = impl std::iter::Iterator<Item = I>;
   9 //~^ ERROR could not find defining uses
  10
  11 impl<T, E> IterBits for T
  12 where
  13     T: std::ops::Shr<Output = T>
  14         + std::ops::BitAnd<T, Output = T>
  15         + std::convert::From<u8>
  16         + std::convert::TryInto<u8, Error = E>,
  17     E: std::fmt::Debug,
  18 {
  19     type BitsIter = IterBitsIter<T, E, u8>;
  20     fn iter_bits(self, n: u8) -> Self::BitsIter {
  21     //~^ ERROR defining opaque type use does not fully define opaque type
  22         (0u8..n)
  23             .rev()
  24             .map(move |shift| ((self >> T::from(shift)) & T::from(1)).try_into().unwrap())
  25     }
  26 }
  27
  28 fn main() {}