Associated types aren't normalized with impl cycles #31593

Activity

1. strega-nil

   changed the title [-]Associated types aren't lowered with looped impls[/-] [+]Associated types aren't normalized with looped impls[/+] on Feb 12, 2016
2. strega-nil

   changed the title [-]Associated types aren't normalized with looped impls[/-] [+]Associated types aren't normalized with impl cycles[/+] on Feb 12, 2016
3. strega-nil commented on Feb 12, 2016

   

   strega-nil

   on Feb 12, 2016

   ContributorAuthor

   More actions

   Honestly, it probably just needs a better error message.
4. eddyb commented on Feb 12, 2016

   

   eddyb

   on Feb 12, 2016

   Contributor

   More actions

   This seems related to #29859, but not... actually working?
   AFAICT, <T as Doop> in the impl<T: Doop> of Doop for T cannot refer to the same impl.

   cc @nikomatsakis
5. strega-nil commented on Feb 12, 2016

   

   strega-nil

   on Feb 12, 2016

   ContributorAuthor

   More actions

   @eddyb looks like the forest may have fixed this? #30533
6. steveklabnik

   added

   A-associated-itemsArea: Associated items (types, constants & functions)Area: Associated items (types, constants & functions)

   on Feb 15, 2016
7. Mark-Simulacrum

   added

   C-bugCategory: This is a bug.Category: This is a bug.

   on Jul 24, 2017
8. oli-obk commented on Jan 25, 2020

   

   oli-obk

   on Jan 25, 2020

   Contributor

   More actions

   The error message seems reasonable to me now as we get

   error[E0053]: method `badoowop` has an incompatible type for trait
    --> src/main.rs:9:26
     |
   3 |     fn badoowop(self) -> Self::Shaboom;
     |                          ------------- type in trait
   ...
   9 |     fn badoowop(self) -> Self {
     |                          ^^^^ expected associated type, found type parameter
     |
     = note: expected type `fn(T) -> <T as Doop>::Shaboom`
                found type `fn(T) -> T`
     = note: you might be missing a type parameter or trait bound
   

   Please reopen if you disagree
9. oli-obk

   closed this as completedon Jan 25, 2020