[Haskell-cafe] Matching constructors

Creighton Hogg wchogg at primula.hep.wisc.edu
Fri Feb 10 11:14:16 EST 2006


Hi,
If I have something like
data Patootie = Pa Int | Tootie Int
and I want to pull out the indices of all elements of a list 
that have type constructor Tootie, how would I do that?

I thought I might be able to use findIndices, but I don't 
know how to express the predicate.


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