error[E0407]: method `line_stream` is not a member of trait `X`
  --> $DIR/ice-unexpected-param-type-whensubstituting-in-region-112823.rs:29:5
   |
LL |     fn line_stream<'a, Repr>(&'a self) -> Self::LineStreamFut<'a, Repr> {}
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not a member of trait `X`

error[E0049]: associated type `LineStream` has 0 type parameters but its trait declaration has 1 type parameter
  --> $DIR/ice-unexpected-param-type-whensubstituting-in-region-112823.rs:25:21
   |
LL |     type LineStream<'a, Repr>
   |                     --  ----
   |                     |
   |                     expected 1 type parameter
...
LL |     type LineStream<'c, 'd> = impl Stream;
   |                     ^^  ^^
   |                     |
   |                     found 0 type parameters

error: unconstrained opaque type
  --> $DIR/ice-unexpected-param-type-whensubstituting-in-region-112823.rs:25:31
   |
LL |     type LineStream<'c, 'd> = impl Stream;
   |                               ^^^^^^^^^^^
   |
   = note: `LineStream` must be used in combination with a concrete type within the same impl

error[E0271]: type mismatch resolving `<Y as X>::LineStreamFut<'a, Repr> normalizes-to ()`
  --> $DIR/ice-unexpected-param-type-whensubstituting-in-region-112823.rs:29:43
   |
LL |     fn line_stream<'a, Repr>(&'a self) -> Self::LineStreamFut<'a, Repr> {}
   |                                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ types differ

error[E0271]: type mismatch resolving `<Y as X>::LineStreamFut<'a, Repr> normalizes-to _`
  --> $DIR/ice-unexpected-param-type-whensubstituting-in-region-112823.rs:29:73
   |
LL |     fn line_stream<'a, Repr>(&'a self) -> Self::LineStreamFut<'a, Repr> {}
   |                                                                         ^^ types differ

error[E0271]: type mismatch resolving `<Y as X>::LineStreamFut<'a, Repr> normalizes-to _`
  --> $DIR/ice-unexpected-param-type-whensubstituting-in-region-112823.rs:29:5
   |
LL |     fn line_stream<'a, Repr>(&'a self) -> Self::LineStreamFut<'a, Repr> {}
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ types differ

error: aborting due to 6 previous errors

Some errors have detailed explanations: E0049, E0271, E0407.
For more information about an error, try `rustc --explain E0049`.