Eri*_*son 6 haskell pointfree dot-operator
我想在haskell中编写一个无点函数,为了简单起见,我想说要创建这个函数:
maxmin :: Ord a => a -> a -> a -> a
maxmin a b c = max a (min b c)
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我可以改进这个
maxmin a b = (max a) . (min b)
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但有没有办法摆脱a和b?
我不会说这更简单但是你走了:
maxmin :: Ord a => a -> a -> a -> a
maxmin = (. min) . (.) . max
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(使用pl来自lambdabot http://www.haskell.org/haskellwiki/Pointfree的工具生成)
lambdabot> pl maxmin a b c = max a (min b c)
maxmin = (. min) . (.) . max
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