process-conduit

Conduits for Processes

Monthly Downloads: 25

Programming language: Haskell

License: BSD 3-clause "New" or "Revised" License

Tags: System     Conduit    

Latest version: v1.2.0.1

README

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 GSource m ByteString and GConduit 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 Data.Conduit
import qualified Data.Conduit.Binary as CB
import Data.Conduit.Process
import System.IO

main :: IO ()
main = runResourceT $ do
  sourceCmd "ls" $= conduitCmd "sort" $$ 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|] $$ CB.sinkHandle stdout

• Unquoting (syntax is same as shakespeare-text)

main = do
  [url] <- getArgs
  print =<< [cmd|curl #{url}|]