(╯°□°）╯︵ ןןǝʞsɐɥ

gistfile1.txt

me@le-me $ cat scratch.hs
evenSum :: Integral a => [a] -> a
evenSum l = accumSum 0 l
            where
              accumSum n [] = n
              accumSum n (x:xs) =
                if even x
                   then accumSum (n+x) xs
                   else accumSum x xs

evenSum' :: Integral a => [a] -> a
evenSum' l = accumSum 0 l
    where
        accumSum n [] = n
        accumSum n (x:xs) =
             if even x
                then accumSum (n+x) xs
                else accumSum n xs

main = do
  print $ evenSum [1..5]
  print $ evenSum' [1..5]

me@le-me $ ./scratch
5
6

-- "The only winning move is not to play." -Joshua
import Data.List
evenSum''' :: Integral a => [a] -> a
evenSum''' l = foldl' (+) 0 (filter even l)
-- haskell ノ( º _ ºノ)