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{-# LANGUAGE DeriveGeneric, TypeOperators, TypeFamilies #-}
import Data.MemoTrie
import GHC.Generics (Generic)
data Color = RGB Int Int Int
| NamedColor String
deriving (Generic)
instance HasTrie Color where
newtype (Color :->: b) = ColorTrie { unColorTrie :: Reg Color :->: b }
trie = trieGeneric ColorTrie
untrie = untrieGeneric unColorTrie
enumerate = enumerateGeneric unColorTrie
runColor (RGB r g b) = r + g + b
runColor (NamedColor s) = length [1..10e7]
runColorMemoized = memo runColor
main =
do putStrLn "first call (should take a few seconds): "
print$ runColorMemoized (NamedColor "")
putStrLn "cached call (should be instantaneous): "
print$ runColorMemoized (NamedColor "")
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