ResumableSource example

gistfile1.hs

import           Control.Monad.IO.Class
import           Data.Conduit
import           Data.Conduit.Binary    as B
import           Data.Conduit.List      as L
import           Data.Char
import           Data.Word

{-
% cat input.txt
upload
1
hello
-}

nl :: Word8
nl = fromIntegral (ord '\n')

main = do
  runResourceT $ do
    let s = sourceFile "input.txt" -- $= B.lines
    (next, head) <- s $$+ (B.takeWhile (/= nl) >+> L.consume) -- (B.lines >+> L.take 1)
    liftIO $ print head
    rest <- next $$+- L.consume
    liftIO $ print rest

{-
-- OUTPUT:
["upload"]
["\n1\nhello\n"]
-}