Difference between revisions of "Talk:Roll your own IRC bot"

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I had the same problem. You can't really forkIO directly from inside the Reader monad, even with liftIO. I ended up with this but maybe there is a better way:
 
I had the same problem. You can't really forkIO directly from inside the Reader monad, even with liftIO. I ended up with this but maybe there is a better way:
 
   
 
privmsgIO :: Handle -> String -> IO ()
 
privmsgIO :: Handle -> String -> IO ()
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and use the IO variant of privmsg.
 
and use the IO variant of privmsg.
  +
  +
This works for some things but I'm not sure what'd be the cleanest way to get information back to the main thread from the forkIO'd commands.
   
 
--[[User:Nurpax|Nurpax]] 16:20, 8 April 2012 (UTC)
 
--[[User:Nurpax|Nurpax]] 16:20, 8 April 2012 (UTC)

Revision as of 16:25, 8 April 2012

Thanks for this useful tutorial! I implemented the normal chat functionality using forkIO as suggested but I'm not happy with my solution. Where would you put the call to forkIO? And how would you write the function that you pass it? Is it possible to somehow use privmsg in this function or do I have to duplicate that code more or less? --Gog 19:09, 18 January 2007 (UTC)

I had the same problem. You can't really forkIO directly from inside the Reader monad, even with liftIO. I ended up with this but maybe there is a better way:

privmsgIO :: Handle -> String -> IO ()
privmsgIO h s =
  writeIO h "PRIVMSG" (botChan ++ " :" ++ s)
-- Send a privmsg to the current chan + server
privmsg :: String -> IrcBot ()
privmsg s = do
  h <- asks socket
  liftIO $ privmsgIO h s

then when I need to forkIO, I do

foo = do
  h <- asks socket
  liftIO $ forkIO (privmsg h ...)

and use the IO variant of privmsg.

This works for some things but I'm not sure what'd be the cleanest way to get information back to the main thread from the forkIO'd commands.

--Nurpax 16:20, 8 April 2012 (UTC)

Btw, I would highly recommend modifying the connect to set the socket encoding to UTF-8:

-- Connect to the server and return the initial bot state
connect :: IO IrcBotRO
connect = notify $ do
  h <- connectTo server (PortNumber port)
  hSetEncoding h utf8

It took me a while to debug why my UTF8 output was all messed up. --Nurpax 16:21, 8 April 2012 (UTC)