[Haskell-cafe] Mapping a list of functions

Tillmann Rendel rendel at Mathematik.Uni-Marburg.de
Thu Jun 17 15:14:26 EDT 2010

Martin Drautzburg wrote:
> The standard map function applies a single function to a list of arguments. 
> But what if I want to apply a list of functions to a single argument. 

So your list of arguments is actually a list of functions. But since 
functions are first-class values, that shouldn't be a problem. You 
simply have to write a appropriate function to map over that list of 

   map (\f -> f a b c) listOfFunctions

The lambda expression (\f -> f a b c) denotes a function which takes a 
function f, and applies it to some values a, b and c. That's exactly the 
function you want to map over the list of functions.

Alternatively, you might want to look into list comprehensions:

   [f a b c | f <- listOfFunctions]

Enjoy Haskell!


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