使用haskell中的多模式缩短函数定义

Question

做得更好:

charToAction 'q' = Just $ WalkRight False
charToAction 'd' = Just $ WalkRight True
charToAction 'z' = Just Jump
charToAction _ = Nothing

要么

charToAction x = case x of
    'q' -> Just $ WalkRight False
    'd' -> Just $ WalkRight True
    'z' -> Just Jump
    _ -> Nothing

？

Answer 1

绝对没有任何功能差异.这是个人喜好的问题.