Use GeneralizedNewtypeDeriving to automatically create associated type families
Here's a simple example:
class C a where
type T a
instance C Int where
type T Int = Bool
newtype NT = NT Int
deriving C
Trac metadata
Trac field | Value |
---|---|
Version | 7.6.3 |
Type | FeatureRequest |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |