1 2 3 4 5 | module Alph where comb :: [a] -> [b] -> [c] -> [(a, b ,c)] comb x y z = concatMap concat $ map (\v -> map (\u -> map ((,,) u v) z) x) y |
5:3: Warning: Fuse concatMap/map
Found:
concatMap concat $ map (\ v -> map (\ u -> map ((,,) u v) z) x) y
Why not:
concatMap (concat . (\ v -> map (\ u -> map ((,,) u v) z) x)) y