Haskell/解決方案/縮排

使用顯式字元代替縮排

練習

使用顯式花括號和分號重寫控制結構章節中的這段程式碼

doGuessing num = do
  putStrLn "Enter your guess:"
  guess <- getLine
  case compare (read guess) num of
    LT -> do putStrLn "Too low!"
             doGuessing num
    GT -> do putStrLn "Too high!"
             doGuessing num
    EQ -> putStrLn "You Win!"

當然，有很多有效的答案，因為您可以隨意縮排程式碼並換行。以下是一個示例

doGuessing num = do {
  putStrLn "Enter your guess:";
  guess <- getLine;
  case compare (read guess) num of {
    LT -> do {
      putStrLn "Too low!";
      doGuessing num;
    };
    GT -> do {
      putStrLn "Too high!";
      doGuessing num;
    };
    EQ -> putStrLn "You Win!";
  };
};