copilot-3.0.1: Examples/Counter.hs

{-# LANGUAGE RebindableSyntax #-}

module Latch where

import Language.Copilot
import Copilot.Compile.C99

import Prelude hiding ((++), (==), mod)

-- A resettable counter
counter :: Stream Bool -> Stream Bool -> Stream Int32
counter inc reset = cnt
  where
    cnt = if reset then 0
          else if inc then z + 1
               else z
    z = [0] ++ cnt

-- Counter that resets when it reaches 256
bytecounter :: Stream Int32
bytecounter = counter true reset where
  reset = counter true false == 256

spec :: Spec
spec = trigger "counter" true [arg $ bytecounter]

main :: IO ()
main = reify spec >>= compile "latch"