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Haskell function that alternatively applies input unary functions

I am trying to write a Haskell function that takes two unary functions (f and g) and a list of numbers (ns) and alternatively applies those input functions f and g to the elements of the inputted list.

For example:

func double square [2, 3, 4, 5, 6]

would return

[4, 9, 8, 25, 12]

I am using WinGHCi for my compiler. Any help on writing this function would be appreciated, thanks.

Solution

  • If you don't want to use any library functions, you can do this by using recursion:

    func _ _ []     = []
func f g (x:xs) = f x : func g f xs