ivory-examples-0.1.0.3: examples/Coroutine.hs

{-# LANGUAGE DataKinds #-}
{-# LANGUAGE TypeOperators #-}

module Coroutine where

import Ivory.Language
import Ivory.Compile.C.CmdlineFrontend

-- No-op "action" for the coroutine to trigger
emit :: Def ('[Sint32] ':-> ())
emit = proc "emit" $ \ _ -> body $ retVoid

sequenced :: Coroutine ('Stored Sint32)
sequenced = coroutine "sequenced" $ CoroutineBody $ \ yield -> do
  forever $ do
    call_ emit 1
    v <- yield >>= deref
    ifte_ (v ==? 1) breakOut (return ())
  call_ emit 2
  forever $ do
    v <- yield >>= deref
    ifte_ (v ==? 2)
      (call_ emit 3)
      (call_ emit 2)

run :: Def ('[IBool, ConstRef s ('Stored Sint32)] ':-> ())
run = proc "run" $ \ doInit arg -> body $ coroutineRun sequenced doInit arg

cmodule :: Module
cmodule = package "sequenced" $ do
  incl emit
  incl run
  coroutineDef sequenced

main :: IO ()
main = compile [cmodule] []