関数プログラミングが 教えてくれる規律1 2 1 3 2 4 2 5 6 7 8 9 10 11 12 Haskell 13 14 Haskell 15 16 ( ) 17 ) 30 18 static 19 (IORef) 20 21 OK NG 22 Haskell (+) :: Num a => a -> a -> a sort :: Ord a => [a] -> [a] delete :: Eq a => a -> [a] -> [a] hGetLine :: Handle -> IO String writeFile :: FilePath -> String -> IO () writeIORef :: IORef a -> a -> IO () IO IO 23 24 1) Ruby 25 1) Haskell 26 2) > split " foo bar baz " ["foo","bar","baz"]
