haskell - This code is supposed to find a single Int in a list that is not dividable by 3 and then say False - 


test4 :: [int] -> bool test4 [] = false test4 (x:xs)    | mod x 3 /= 0 = false    | otherwise = true

i'd code find (not first) number of list can't divided three, , false.

i started learning haskell.

you need keep searching list if encounter number divisible 3. otherwise clause needs recursively call function.

test4 :: [int] -> bool test4 [] = true test4 (x:xs)    | mod x 3 /= 0 = false    | otherwise = test4 xs

but i'd advise avoid writing low-level pattern-matching-and-recursion code when can. haskell's high-level language! in plain english, want function test whether of elements in list divisible 3. that's all :: (a -> bool) -> [a] -> bool function for:

test4 = (\x -> x `mod` 3 == 0)

i think version clearer , easier read, being shorter.


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