的開發文件代碼: data Person = Person { firstName :: String
, lastName :: String
, age :: Int
} deriving (Eq, Show, Read)
編譯: *Main> :load "/home/optimight/baby.hs"
[1 of 1] Comp
*Main> :t putStrn
<interactive>:1:1:
Not in scope: `putStrn'
Perhaps you meant one of these:
`putStr' (imported from Prelude),
`putStrLn' (imported from Prelude) 請注意,我正在用haskell模式在emacs中