first task solution from https://projecteuler.net in haskell

task1.hs

{-
    #1 task from https://projecteuler.net/archives
Find the sum of all the multiples of 3 or 5 below 1000.

-}
mult::Int -> Bool
mult x = x `mod` 5 == 0 || x `mod` 3 == 0

filter_seq::[Int] -> [Int]
filter_seq seq = [x | x <- seq, mult x ]

main::IO()
main = print (sum $ filter_seq [0..999])