Haskell cartesian product of infinite lists

Question

I want to generate a vectorspace from a basis pair, which looks something like:

genFromPair (e1, e2) = [x*e1 + y*e2 | x <- [0..], y <- [0..]]

Answer 1

Using the diagonal snippet from CodeCatalog:

genFromPair (e1, e2) = diagonal [[x*e1 + y*e2 | x <- [0..]] | y <- [0..]]

diagonal :: [[a]] -> [a]
diagonal = concat . stripe
    where
    stripe [] = []
    stripe ([]:xss) = stripe xss
    stripe ((x:xs):xss) = [x] : zipCons xs (stripe xss)

    zipCons [] ys = ys
    zipCons xs [] = map (:[]) xs
    zipCons (x:xs) (y:ys) = (x:y) : zipCons xs ys