haskell - Apply a function to a list of items -

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I have defined a function f which will be given value Item is x stored inside a list of prices with [code] [[string, string, ante]] 

  a = string x = String value = int prices list = [(a, x, price)] fax ((a1, x1, price): ys). A == A1 & amp; Amp; X == x1 = value | Otherwise = FA x YS   
 I have to apply this function in a list of items, but I'm stuck. Is it possible to use the map? I can not get it.  
 (Only functions that can use recursion f)  
  Edit to clarify some examples   
 < Code> pricesList = [("Apple", "iPod", 100), ("Apple", "iPhone", 200), ("Samsung", "Galaxy", 200)] Passure = [("Harry", 1 9 85, "Apple", ["iPhone", "iPod"]), ("George", 1983, "Samsung", ["Galaxy"])] * Main & gt;   
 I should know how much money has been spent by defining a new function, assuming that  spent  code> F  Inside of it)  
  * main & gt; "Its what's up to now"  
  itsThePerson name (n, _, _, _) = name == n InfoFrom name = (head filter (its peers name)) Money brand (_ , _, B, _) = B product (_, _, _, P) = P brand = brand = brand InfoPerson = info from the product infoFrom   
 Is it possible to use  map  with  f  to know the sum of the prices?  
 (function  f  will be  itemprice )  
  spent name = sum (map (itemprice (branding Name of the Xxx Prices List (Name of the Product)   
 Am I thinking about it in the right direction?   
 
 
 Assume that you have three logic functions:  
  f :: a -> gt - b -> c -> D   
 and  c  list of values ​​-  list :: [b] . Suppose that we have each  f < / Code> want to apply list Item with default and first arguments, so we can do something like this:  
  map (fxy) list   
 where  x :: a  and  y :: b .  
 In your case the only difference is the sequence of arguments. For such issues,  flip :  
  flip :: (a -> - - C) -> (b -> - - C) - basic function F :: a - & gt; be - & gt; C -> D - Particle Application Fx :: B - & gt; C -> D Flip Flip (FX) :: C -> B - & gt; D - Particle application again (Flip (FX) y) :: B - & gt; d map (flip (fx) y) list :: [D]   
 In your case this will probably give some results in the map (flip (FA) prices .

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