N-ary zipWith: http://www.brics.dk/RS/01/10/BRICS-RS-01-10.pdf

ZipWith.hs

module Data.ZipWith where

import Prelude hiding (zipWith, succ)

infixl 5 <<
(<<) :: [a -> b] -> [a] -> [b]
(f:fs) << (a:as) = f a : (fs << as)
_      << _      = []

succ :: ([b] -> c) -> [a -> b] -> [a] -> c
succ = \n fs as -> n (fs << as)

zero  :: a -> a
zero  = id
one   = succ zero
two   = succ one
three = succ two
four  = succ three
five  = succ four
six   = succ five
seven = succ six
eight = succ seven

zipWith :: ([a] -> b) -> a -> b
zipWith n f = n (repeat f)

-- example
ex1 = zipWith eight f as1 as2 as3 as4 as5 as6 as7 as8
  where
  as1 = [1]
  as2 = [2]
  as3 = [3]
  as4 = [4]
  as5 = [5]
  as6 = [6]
  as7 = [7]
  as8 = [8]
  f a b c d e g h i = a + b + c + d + e + g + h + i