[Haskell-cafe] IO inside CGI

[Adrian Neumann]

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I'm toying around with web programming in Haskell. I'm trying to write a
script which GETs an id and returns a couple of random numbers.
Something like this:

cgiMain :: CGI CGIResult
cgiMain = do
	inp <- getInput "id"
	let gen = parse inp
	output $ take 10 (randoms gen)

parse :: Maybe String-> StdGen
parse (Just x) = read x
parse Nothing = undefined

Now I'd like to get a new StdGen, in case no id was supplied to the script.

cgiMain :: CGI CGIResult
cgiMain = do
	inp <- getInput "id"
	gen <- parse inp
	output $ take 10 (randoms gen)

parse :: Maybe String-> IO StdGen
parse (Just x) = return $ read x
parse Nothing = getStdGen

Obviously this doesn't work because I'm trying to do IO inside CGI
(right?). Is there some incantation I can perform to make this possible?
Like

gen <- arcaneMagic parse inp

As you probably have noticed I don't know very much about monads, all I
did until now was reading or writing some files.

Thanks in advance
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