id,summary,reporter,owner,description,type,status,priority,milestone,version,resolution,keywords,cc
8,Problems with filterMP,pierre,somebody,"This sample code generates rather strange results: 

{{{
import FRP.Reactive as R
import FRP.Reactive.LegacyAdapters
    
import Control.Applicative

import Control.Monad
import Data.Monoid
import Control.Concurrent
import System.IO

main = do
  c <- makeClock 
  (onStanza, snk_onS) <- makeEvent c
  let bred = ((const $ putStrLn "">10"") <$> filterMP (>10) onStanza) `mappend`
             ((const $ putStrLn ""<10"") <$> filterMP (<10) onStanza)
  hSetBuffering stdout NoBuffering
  doSched c connect bred
  mapM (\x -> snk_onS x >> threadDelay 1000) [5..15]
  forever $ threadDelay 1000000000
  return ()

doSched clock init act = do
  updater <- mkUpdater (cGetTime clock) (stepper init act)
  forkIO $ forever $ (updater)
}}}

After displaying: 
{{{
<10
<10
}}} 
everything hangs. Debugging shows that sink and updater are called, but updater does nothing. 

Same code without filterMP works as expected: it displays 20 messages. ",defect,new,critical,,,,,