[Haskell-beginners] How to extract from Maybe & Either in GHCi
chrisdone at googlemail.com
Thu Apr 14 02:19:15 CEST 2011
On 14 April 2011 00:52, <blackcat at pro-ns.net> wrote:
> Pattern matching works in ghci:
>> let x = Just (Left (Blah [stuff]))
>>> let (Just (Left (Blah y)) = x
> Thanks! That's exactly what I'm looking for.
FWIW there is also Data.Either which has the either function.
λ> :t either
either :: (a -> c) -> (b -> c) -> Either a b -> c
Quite useful sometimes.
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