A zip function in Haskell that stops zipping when any of the input lists' first element is zero, or when any of the input list is empty.

zip_no_zero.hs

--As modified from the Prelude:
zip_no_zero ::(Num a, Eq a, Num b, Eq b)=> [a] -> [b] -> [(a,b)]
zip_no_zero []     _bs    = []
zip_no_zero _as    []     = []
--Add to p: when any of the input lists' first element is zero.
zip_no_zero (0:as) _bs    = []
zip_no_zero _as    (0:bs) = []

zip_no_zero (a:as) (b:bs) = (a,b) : zip_no_zero as bs

main = do
  print (zip_no_zero [0,1,2] [1,2,3])
  print (zip_no_zero [1,2,3,4,0,5,6] [1,2,3,4,5,6,0])

See my blog post.