src/test/ui/associated-types/issue-67684.rs

   1 // check-pass
   2
   3 #![allow(dead_code)]
   4
   5 trait ParseError {
   6     type StreamError;
   7 }
   8
   9 impl<T> ParseError for T {
  10     type StreamError = ();
  11 }
  12
  13 trait Stream {
  14     type Item;
  15     type Error: ParseError;
  16 }
  17
  18 trait Parser
  19 where
  20     <Self as Parser>::PartialState: Default,
  21 {
  22     type PartialState;
  23     fn parse_mode(_: &Self, _: Self::PartialState) {
  24         loop {}
  25     }
  26 }
  27
  28 impl Stream for () {
  29     type Item = ();
  30     type Error = ();
  31 }
  32
  33 impl Parser for () {
  34     type PartialState = ();
  35 }
  36
  37 struct AndThen<A, B>(core::marker::PhantomData<(A, B)>);
  38
  39 impl<A, B> Parser for AndThen<A, B>
  40 where
  41     A: Stream,
  42     B: Into<<A::Error as ParseError>::StreamError>,
  43 {
  44     type PartialState = ();
  45 }
  46
  47 fn expr<A>() -> impl Parser
  48 where
  49     A: Stream<Error = <A as Stream>::Item>,
  50 {
  51     AndThen::<A, ()>(core::marker::PhantomData)
  52 }
  53
  54 fn parse_mode_impl<A>()
  55 where
  56     <A as Stream>::Error: ParseError,
  57     A: Stream<Error = <A as Stream>::Item>,
  58 {
  59     Parser::parse_mode(&expr::<A>(), Default::default())
  60 }
  61
  62 fn main() {}