Polysemy.Process.Effect.Process

Documentation

data Process i o e :: Effect where

Abstraction of a process with stdinstdoutstderr.

This effect is intended to be used in a scoped manner:

import Polysemy.Resume
import Polysemy.Conc
import Polysemy.Process
import qualified System.Process.Typed as System

prog :: Member (Scoped resource (Process Text Text e !! err)) r => Sem r Text
prog =
 withProcess do
   resumeAs "failed" do
     send "input"
     recv

main :: IO ()
main = do
  out <- runConc $ interpretProcessNative (System.proc "cat" []) prog
  putStrLn out

Constructors

Recv :: Process i o e m o

RecvError :: Process i o e m e

Send :: i -> Process i o e m ()

Instances

type DefiningModule Process

Defined in Polysemy.Process.Effect.Process

type DefiningModule Process = "Polysemy.Process.Effect.Process"

recv :: forall i o e r. Member (Process i o e) r => Sem r o

Obtain a chunk of stdout.

recvError :: forall i o e r. Member (Process i o e) r => Sem r e

Obtain a chunk of stderr.

send :: forall i o e r. Member (Process i o e) r => i -> Sem r ()

Send data to stdin.

withProcess :: forall resource i o e err r. Member (Scoped resource (Process i o e !! err)) r => InterpreterFor (Process i o e !! err) r

Create a scoped resource for Process.