[Haskell-beginners] help with types and composition

[Britt Anderson]

I would like to write a function that takes two lists of numbers and 
returns a number. For simplicity, let's assume an integer, i.e.
myfunc:: [Integer]->[Integer]->Integer
But I can't quite get things right when trying to
define myfunc = ...
 and making the arguments implicit.

My difficulty might be seen with the following two functions,
let,

f1 = (zipWith ($)) . (map  (*))

f2 = sum


if I set the types such that f1 returns [Integer] and sum accepts 
[Integer] it seems that somehow I should be able to compose them in to a 
single function that takes two lists and returns the number, but f1 . f2 
and numerous variations don't work. I can curry some list l and f1 . (f2 
l) works, but is there a way to get f1 and f2 combined into a function 
that accepts two lists?


My problem is not really about writing the function but about 
composition. I can write the function with arguments or a local lambda  
that suits my practical purpose. But the fact that I think I should be 
able to compose f1 . f2 somehow reveals a conceptual misunderstanding 
that I hope someone will help me clear up.

Thank you,
Britt Anderson
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