Hello all, I added a few new features to the experimental branch of Elerea [1], my little FRP library. The previous release added random sources -- both noise signals and instantaneous values within generators -- using mersenne-random, and the current update added an extra primitive to handle external events that can occur several times between samplings, as I heard some people needed this. All the three variants of the experimental interface support these additions. Here's a simple example showing how the new externalMulti construct can be used: import Control.Monad import FRP.Elerea.Experimental.Simple main = do (gen,sink) <- externalMulti sig <- start $ do vals <- gen cnt <- stateful 10 (+1) return (liftM2 (:) cnt vals) let act = print =<< sig act sink 3 act >> act sink 8 >> sink 2 act sink 1 >> sink 7 >> sink 9 act >> act >> act sink 4 act The program prints the following: [10] [11,3] [12] [13,2,8] [14,9,7,1] [15] [16] [17,4] As you can see, all the input received since the last sampling is collected in a list in reverse order. It is up to the programmer to store these values somewhere or build further IO actions out of them. Gergely [1] http://hackage.haskell.org/package/elerea -- http://www.fastmail.fm - Does exactly what it says on the tin