-XTypeInType uses up all memory when used in data family instance
Compiling this code with GHC 8.1 causes all my memory to be used very quickly:
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE TypeInType #-}
module TypeInTypeEatsAllMemory where
import Data.Kind
type Const a b = a
data family UhOh (f :: k1) (a :: k2) (b :: k3)
data instance UhOh (f :: * -> * -> *) (a :: forall a) (b :: Const * a) = UhOh
On the other hand, this code compiles without issue:
{-# LANGUAGE TypeInType #-}
module TypeInTypeEatsAllMemory where
import Data.Kind
type Const a b = a
data UhOh (f :: * -> * -> *) (a :: forall a) (b :: Const * a) = UhOh
Trac metadata
Trac field | Value |
---|---|
Version | 8.1 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | high |
Resolution | Unresolved |
Component | Compiler (Type checker) |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | goldfire |
Operating system | |
Architecture |