Haskell Map definition Error -


I am recently for Haskell and I have a problem while trying to write my definition of the map function. Example: Mapi (& gt; 2) [1,2,3,4,5] = [false, false, true, true] 

  Mapi _ [] = 0 mpeg F (X : Xs) = [fx] ++ mapi f xs   
 When I try this I get an error:  
  any number (number [bool] ]]) Potential Fix: Potential Fix: (Name [Child]) Add an example announcement for: Mapi (> 2) [1, 2, 3, 4, ...] Equation for `this': this = mpei (& gt; 2) [1, 2, 3, ....]   
 I know that it is related: mapi _ [ ] = 0 but I do not know the problem I found it, I mean, he has to stop at []!  
  
 
 
 You accidentally replaced  0  with  []  In the first case it should be  
  mapi _ [] = [] mpeg f (x: x) = [fx] ++ mpeg fx   
 If you type a signature, it helps:  
  mapi :: (a-> b) - & gt; [A] - & gt; [B]   
 then  Mapi  is considered to return the function, a list, and a list  0  is not a list Is, but  []  is.  
 Any example ....  
 The error message is saying that this will be done in  0  in a  [bool]  It was trying to change, which is not it a numerical type, it is stuck because the  Num  class by  fromInteger  function, but  [bool]  . (Each  Num  example should have a  to the integer  function so that the written words containing the integers like  0  and  23  That type of value can stand for.)  
 This shows that you can make an example for  Num [Bool]  so that it can be compiled. This is not a good idea, and this particular error message is often due to a type of mismatch rather than an actual example example - it is worth remembering next time.

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