[Haskell-cafe] Question on a common pattern

[Achim Schneider]

tsuraan <tsuraan at gmail.com> wrote:
> Is there a more concise way to do this?

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.

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