Re: [Haskell-cafe] Question on a common pattern

If you have only one alternative, then you can simply do:

Opt1 <- someIO

E.g., if you are _sure_ that foo returns always a 'Just' within a monad you can perfectly do :

Just x <- foo

That's interesting. I had no idea that one could do that. I think what I'm looking for is something along the lines of lambda-case, but thanks for the tip.