From dustin.deweese at gmail.com  Wed Jan 12 00:32:09 2011
From: dustin.deweese at gmail.com (Dustin DeWeese)
Date: Tue, 11 Jan 2011 18:32:09 -0500
Subject: [reactive] Reactive space leak
Message-ID: <AANLkTi=pJ8=nYYik3EGkoKa=hjdBYLf_D6wW_6b03L3e@mail.gmail.com>

I cannot get Reactive to behave.  I am trying to write a simple program that
feeds events to a function and prints 'DING!' when it receives an event from
the function.  If the function is id or (join . return), it works
correctly.  If the function is (>>= return), it consumes all of my RAM and
does nothing.

Why?  I've spent several days trying to figure this out.

I am using GHC 6.12.1 for x86_64 Linux.

import FRP.Reactive
import FRP.Reactive.Reactive
import FRP.Reactive.Internal.Reactive
import FRP.Reactive.Internal.Timing
import FRP.Reactive.LegacyAdapters
import Control.Monad
import Control.Concurrent
import Control.Applicative

runEventProcessor :: (Event () -> Event ()) -> IO ()
runEventProcessor f = do
  clk <- makeClock
  (sink, ev) <- makeEvent clk
  forkE (wait clk) . fmap (\_ -> putStrLn "DING!") . f $ ev
  forever $ do getLine -- wait for <ENTER>
               sink ()
               putStrLn "<< button pressed >>"
               threadDelay 100000 -- avoid pressing button too fast

wait clk = sleepPast (cGetTime clk) . exactNB

explodes1 = runEventProcessor (>>= return)
explodes2 = runEventProcessor (join . fmap (Event . pure . pure))
works1 = runEventProcessor (join . return)
works2 = runEventProcessor (fmap id)
works3 = runEventProcessor (join . Event . pure . pure)
-- requires joinE to be exported from FRP.Reactive.PrimReactive
-- works4 = runEventProcessor (joinE . return)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.haskell.org/pipermail/reactive/attachments/20110111/b5ab7312/attachment.htm>

From conal at conal.net  Wed Jan 12 01:21:29 2011
From: conal at conal.net (Conal Elliott)
Date: Tue, 11 Jan 2011 16:21:29 -0800
Subject: [reactive] Reactive space leak
In-Reply-To: <AANLkTi=pJ8=nYYik3EGkoKa=hjdBYLf_D6wW_6b03L3e@mail.gmail.com>
References: <AANLkTi=pJ8=nYYik3EGkoKa=hjdBYLf_D6wW_6b03L3e@mail.gmail.com>
Message-ID: <AANLkTinxgH9nTMib=sRRyhVOa5H3TPGeE9eOaDg5M_6B@mail.gmail.com>

Hi Dustin,

Sorry about that. There are some serious space leaks no one has figured out
yet (afaik). :(

    - Conal

On Tue, Jan 11, 2011 at 3:32 PM, Dustin DeWeese <dustin.deweese at gmail.com>wrote:

> I cannot get Reactive to behave.  I am trying to write a simple program
> that feeds events to a function and prints 'DING!' when it receives an event
> from the function.  If the function is id or (join . return), it works
> correctly.  If the function is (>>= return), it consumes all of my RAM and
> does nothing.
>
> Why?  I've spent several days trying to figure this out.
>
> I am using GHC 6.12.1 for x86_64 Linux.
>
> import FRP.Reactive
> import FRP.Reactive.Reactive
> import FRP.Reactive.Internal.Reactive
> import FRP.Reactive.Internal.Timing
> import FRP.Reactive.LegacyAdapters
> import Control.Monad
> import Control.Concurrent
> import Control.Applicative
>
> runEventProcessor :: (Event () -> Event ()) -> IO ()
> runEventProcessor f = do
>   clk <- makeClock
>   (sink, ev) <- makeEvent clk
>   forkE (wait clk) . fmap (\_ -> putStrLn "DING!") . f $ ev
>   forever $ do getLine -- wait for <ENTER>
>                sink ()
>                putStrLn "<< button pressed >>"
>                threadDelay 100000 -- avoid pressing button too fast
>
> wait clk = sleepPast (cGetTime clk) . exactNB
>
> explodes1 = runEventProcessor (>>= return)
> explodes2 = runEventProcessor (join . fmap (Event . pure . pure))
> works1 = runEventProcessor (join . return)
> works2 = runEventProcessor (fmap id)
> works3 = runEventProcessor (join . Event . pure . pure)
> -- requires joinE to be exported from FRP.Reactive.PrimReactive
> -- works4 = runEventProcessor (joinE . return)
>
>
> _______________________________________________
> Reactive mailing list
> Reactive at haskell.org
> http://www.haskell.org/mailman/listinfo/reactive
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.haskell.org/pipermail/reactive/attachments/20110111/e537cffb/attachment.htm>