Re: [Haskell-cafe] A simple beginner question

On Tue, Jun 3, 2008 at 6:48 PM, Ronald Guida wrote:

filter (\x -> case x of A -> True; otherwise -> False) sampleTypes ==> [A]

filter (\x -> case x of B _ -> True; otherwise -> False) sampleTypes ==> [B 5]

There's a neat little mini-trick for these types of pattern matches: filter (\x -> case x of B {} -> True; otherwise -> False) sampleTypes Does the same thing, but works no matter how many arguments the constructor B takes. Luke