{-# LANGUAGE TemplateHaskell #-}
{-# LANGUAGE StrictData #-}
module MaybeHelp where
import Control.Lens

-- | Strict maybe
data Maybe' a 
    = Just' {__Just' :: a }
    | Nothing'

fromJust' :: Maybe' a -> a
fromJust' mx = case mx of
    Just' x -> x
    Nothing' -> error "no fromJust'"
makeLenses ''Maybe'