[Haskell-cafe] Re: Is StateT what I need?

Andre Nathan wrote:

Hello (Newbie question ahead :

I tried this for insertProc, but it obviously doesn't work... what would be the correct way to do this?

...

insertProc :: Pid -> StateT PsMap IO PsInfo insertProc pid = do proc <- procInfo pid -- XXX this is obviously wrong... psMap <- get put (Map.insert pid proc psMap) return (proc)

I see that using "lift" makes it compile (Control.Monad.Trans.lift):

insertProc pid = do proc <- lift (procInfo pid)