On Fri, Feb 4, 2011 at 9:41 AM, C K Kashyap
Thanks Steffen,
Prelude> :l MyModule.hs *MyModule> conn <- waitForAndAcceptConnection *MyModule> someData <- getSomeData conn *MyModule> sendSomeAnswer conn $ processSomeData someData ...
So this cycle of getting data from the connection and writing answer on the connection should happen concurrently with the ghci interaction ... so lets say that when the "thread" is forked that listens on socket behaves like an echo server ... as in, it reads data from the client till "\n" and echoes it back ... All this would happen without the intervention of the user using GHCI ... However, using GHCI, the user should be able to modify the code such that the server returns "hello" prepended to the input. ..
startMyServer -- at this point the the echo server gets spawned -- echo server continues to run someFunction "hello" --- now onwards hello gets prepended --- echo server continues to run returning "hello" prepended someFunction "world" --- now onwards "helloworld" get I hope this is possible without having to modify ghci itself.
Something like this, perhaps. Sorry that it is a bit hard to read. Anthony $ ghci GHCi, version 6.12.3: http://www.haskell.org/ghc/ :? for help Loading package ghc-prim ... linking ... done. Loading package integer-gmp ... linking ... done. Loading package base ... linking ... done. Loading package ffi-1.0 ... linking ... done. Prelude> :m +Data.IORef Control.Concurrent Control.Monad Prelude Data.IORef Control.Concurrent Control.Monad> msg <- newIORef "Hello" Prelude Data.IORef Control.Concurrent Control.Monad> let echo = forever $ readIORef msg >>= putStrLn >> threadDelay 3000000 Prelude Data.IORef Control.Concurrent Control.Monad> t <- forkIO echo Hello Prelude Data.IORef Control.Concurrent Control.Monad> Hello Hello writeIORefHello msg "World" Prelude Data.IORef Control.Concurrent Control.Monad> World World