Use Typeable instead of homegrown WitnessFor for ElemOf

byg/src/Function.hs

@@ -16,11 +16,12 @@ module Function
 import Prelude hiding (String, FilePath)
 
 import Types.Values
-import Types.Value (Valuable, WitnessFor(..))
+import Types.Value (Valuable)
 import Types.Function
 import Types.Token (Token(..))
 import DependencyGenerator (DepGenM, TokenableTo(..), toTupleToken, runFunction)
 
+import Type.Reflection (Typeable, TypeRep, typeRep)
 import qualified Codec.Picture as CP
 import qualified Codec.Picture.STBIR as CPS
 import Data.Char (toLower)
@@ -76,13 +77,13 @@ lowerString :: TokenableTo String a => a -> DepGenM (Token String)
 lowerString a = runFunction LowerString =<< toToken a
 
 
-data ElemOf a where ElemOf :: WitnessFor w a => w -> ElemOf a
+data ElemOf a where ElemOf :: TypeRep a -> ElemOf a
 deriving instance Show (ElemOf a)
 instance (Show a, Valuable a, Eq a) => IsFunction (ElemOf a) (a, [a]) Bool where
   evalFunction (ElemOf _) (y, ys) = y `elem` ys
 
-elemOf :: forall t w a b. (Show t, Valuable t, Eq t, TokenableTo t a, TokenableTo [t] b, WitnessFor w t) => a -> b -> DepGenM (Token Bool)
-elemOf a b = runFunction (ElemOf (witnessValue :: w)) =<< toTupleToken a b
+elemOf :: forall t a b. (Show t, Valuable t, Eq t, TokenableTo t a, TokenableTo [t] b, Typeable t) => a -> b -> DepGenM (Token Bool)
+elemOf a b = runFunction (ElemOf (typeRep :: TypeRep t)) =<< toTupleToken a b
 
 
 data MakeTemplate = MakeTemplate deriving Show