[Haskell-cafe] Introspection on types.

Derek Elkins derek.a.elkins at gmail.com
Thu Oct 1 19:43:59 EDT 2009

On Thu, Oct 1, 2009 at 6:22 PM, Gregory Propf <gregorypropf at yahoo.com> wrote:
> Is there a way to tell, let's say, how many constructors there are for a type?  Or do I need one of the haskell extensions I've read about?

Use Data.Data and derive Data for the types you are interested in or
instance it for pre-existing types that aren't already instances.
Introspection is tedious but trivial.


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