CountLines.hs

module CountLines where

import           Prelude                         hiding (length, lines,
                                                  readFile)

import           Control.Monad.Trans.Resource    (runResourceT)
import           Data.ByteString.Streaming.Char8 (lines, readFile, toLazy)
import           Streaming                       (mapped)
import           Streaming.Prelude               (fst', length)

countLines :: FilePath -> IO Int
countLines =
    runResourceT . fmap fst' . length . mapped toLazy . lines . readFile

countLinesInFiles :: [FilePath] -> IO Int
countLinesInFiles = fmap sum . traverse countLines