By using ByteString, this program becomes much faster than text/string version.

split_and_count_byte.hs

import qualified Data.ByteString.Char8 as B

-- https://hackage.haskell.org/package/bytestring-0.10.8.1/docs/Data-ByteString-Char8.html
splitBS x y = h : if B.null t then [] else splitBS x (B.drop (B.length x) t) where (h,t) = B.breakSubstring x y

countSplit row = length $ splitBS (B.pack " ||| ") row

readLines = B.getContents >>= (return . B.lines)

countToks lines = foldl (+) 0 (map countSplit lines)

main = readLines >>= (return . countToks) >>= (putStrLn . show)