ConstraintKinds and reifyInstances
reifyInstances doesn't appear to know how to deal with a constraint that is just an alias. For example, the following prints (True,False):
{-# LANGUAGE ConstraintKinds #-}
{-# LANGUAGE TemplateHaskell #-}
import Language.Haskell.TH
import Language.Haskell.TH.Syntax
class C a
instance C Int
type D a = C a
main = print $(
do isCInst <- isInstance ''C [ConT ''Int]
isDInst <- isInstance ''D [ConT ''Int]
lift (isCInst,isDInst))
Trac metadata
Trac field | Value |
---|---|
Version | 7.6.3 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |