Hello cafe!

It seems that this behavior is wrong:

> class Foo a where { type Bar a; baz :: a -> Bar a }

> baz zzz         -- zzz is not in scope

<interactive>:17:1: error:

    • Couldn't match expected type ‘Bar a’ with actual type ‘Bar a0’

      NB: ‘Bar’ is a type function, and may not be injective

      The type variable ‘a0’ is ambiguous

    • In the ambiguity check for the inferred type for ‘it’

      To defer the ambiguity check to use sites, enable AllowAmbiguousTypes

      When checking the inferred type

        it :: forall a. Bar a

As opposite - correct behavior:

> :t negate

negate :: Num a => a -> a

> negate zzz

<interactive>:19:8: error: Variable not in scope: zzz

Best regards,

Dmitry