Cannot declare multiparameter type class with TypeOperators.
This code lead to error message: "Malformed instance header"
{-# LANGUAGE TypeOperators #-}
{-# LANGUAGE MultiParamTypeClasses #-}
class f :<: g
instance () :<: ()
If instance declaration changed to code below it compiles just fine.
instance (:<:) () ()
Trac metadata
Trac field | Value |
---|---|
Version | 6.12.3 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |