Missing ambiguity test for class methods
If you write
type family F a
foo :: F a -> F a
foo = ...
then foo
is rejected as having an ambiguous type. But if instead you write
class C a where
type F a
foo :: F a -> F a
no such test is made. That's inconsistent, and leads to downstream errors (see #8030 (closed) for example). Better to do an ambiguity test.
Trac metadata
Trac field | Value |
---|---|
Version | 7.7 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |