实例显示特定数据

Question

我已经定义了以下类型：

   data Taula = Taula String [[String]]

我创建了以下实例：

instance Show Taula   
   where 
     show  Taula [( n , i , c )]  = show  Taula [( n , i , c )]++ "n" 
     show ( l : ls )  = show l ++  "n"  ++ show ls  

但会生成以下错误：

  Equations for `show' have different numbers of arguments
  lastHaskell.hs:184:18-82
  lastHaskell.hs:185:18-63
  In the instance declaration for `Show Taula'

然后尝试将问题分为以下不同的方法：

  instance Show mostrarTaula where
      show (Taula sep []) = ""
      show (Taula sep (k:lls) ) =  show ([tractar sep k]) ++ "n" 
                                 ++ show (mostrarTaula (Taula sep lls))
--["Hola","Que","fas"] --> "HolakkQuekkfas"
 tractar :: String -> [String] -> String
 tractar sep [] = ""
 tractar sep par = (head par) ++ sep ++ tractar sep (drop 1 par) 
  mostrarTaula :: Taula -> [String] --[[String]] = lls i k=[String]
  mostrarTaula (Taula sep []) = [""]
 mostrarTaula (Taula sep (k:lls) ) =  [tractar sep k] ++ (mostrarTaula(Taula sep lls))

我能做的？我尝试的是打印一个由[（字符串，字符串，字符串）]组成的数据类型？我想以表格形式显示数据。每个元组后用 n。

输出示例：

first element tuple1 Second element tuple1 third element tuple1 first element tuple2 Second element tuple2 third element tuple2 first element tuple3 Second element tuple3 third element tuple3

Answer 1

我不完全理解想要输出是什么，但是也许您可以适应以下内容：

instance Show Taula where
  show (Taula sep []) = ""
  show (Taula sep (k:lls)) = tractar sep k ++ "n" ++ show (Taula sep lls)