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

Quoth Achim Schneider , ...

I use

someIO >>= f where f Opt1 = ...

If it's a common pattern, you can even do

opts f _ _ (Opt1 x) = f x opts _ g _ (Opt2 x) = g x opts _ _ h (Opt3 x) = h x

. Functions are easier to mess around with than case expressions.

I like this ... or, I would like it, if I could make it work! I get "The last statement in a 'do' construct must be an expression", if I don't drag the `where' clause down to the end of the `do' block around `someIO', which of course is what we're trying to avoid with the case expression. I must have missed a trick with the layout? Donn Cave, donn@avvanta.com