Question

Current Code

I have two functions as

f1::Int->Int->Int
f1 a b | a==1 &&  b==1 = 1
       | otherwise = 0

applying this function to a [Int] by a another function

f2::[Int]->[Int]->[Int]
f2 a b = map f1 a b

Error

Type error in application
*** Expression     : map f1 c d
*** Term           : map
*** Type           : (e -> f) -> [e] -> [f]
*** Does not match : a -> b -> c -> d

Conclution

actually what i requied is to apply the f1 which perform to a Int to a [Int] using f2
is this problem can solved in higher order functions ? or any other method ? … or how can i transform f2 to be a higher order function to take f1 ?

Thanks!

Answer 1

If you want to apply the function to two list you need a different function, namely zipWith.

f2 a b = zipWith f1 a b