[Haskell-cafe] Partial pattern matching

John Van Enk vanenkj at gmail.com
Mon Mar 9 13:54:20 EDT 2009


You can use the record syntax to get around some of this:

data P { first :: Int, second :: Int }

firstCoord (P {first = f}) = f

2009/3/9 Peter Verswyvelen <bugfact at gmail.com>

> In Haskell, a data constructor can be used partially applied:
> data Pair a b = P a b
>
> f = P 1
>
> however, I cannot do "partial pattern matching", e.g
>
> firstCoord (P x) = x
>
> does not work.
>
> I guess a very important reason must exist why this is the case?
>
>
>
>
>
>
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>


-- 
/jve
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