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{-# LANGUAGE NoImplicitPrelude #-}
module Foreign.Maybe where
import Data.Bool -- for not
import Data.Function -- for (.)
import Data.Maybe
data CMaybe a
foreign import bpcall "Prelude:cNothing" builtin_cNothing :: () -> CMaybe a
foreign import bpcall "Prelude:" cJust :: a -> CMaybe a
foreign import bpcall "Prelude:" cIsJust :: CMaybe a -> Bool
foreign import bpcall "Prelude:" cFromJust :: CMaybe a -> a
cMaybe Nothing = cNothing
cMaybe (Just x) = cJust x
cNothing = builtin_cNothing ()
cIsNothing = not . cIsJust
fromCMaybe x = if cIsJust x
then Just $ cFromJust x
else Nothing
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