@hackage process-conduit0.4.0

Conduits for processes

process-conduit: Conduit for processes

About

This package provides conduit for processes. Also this provides quasi-quoters for process using it.

Install

$ cabal update
$ cabal install process-conduit

Document

Haddock documents are here:

http://hackage.haskell.org/package/process-conduit

Quasi Quoters

process-conduit has three quasi-quoters, cmd, scmd and ccmd.

The result type of cmd is Lazy ByteString, but execution will perform strictly.

The result type of scmd and ccmd are Source ByteString m ByteString and Conduit ByteString m ByteString respectively.

If a command is failed, an exception is thrown.

Commands are executed in run-time, not compile-time.

Examples

  • Create a Source and a Conduit of process
import qualified Data.Conduit as C
import qualified Data.Conduit.Binary as CB
import Data.Conduit.Process
import System.IO

main :: IO ()
main = C.runResourceT $ do
  sourceCmd "ls" C.$= conduitCmd "sort" C.$$ CB.sinkHandle stdout
  • Invoke a process simply
{-# LANGUAGE QuasiQuotes #-}
import System.Process.QQ

main = print =<< [cmd|ls|]
  • Conduit Quasi-Quoters
main :: IO ()
main = runResourceT $ do
  [scmd|ls|] $= [ccmd|sort|] $$ sinkHandle stdout
main = do
  [url] <- getArgs
  print =<< [cmd|curl #{url}|]