Is it possible to determine the arity of a value&#39;s constructor?<br>Suppose I have a value x of type<br><br>  data A = B Int | C<br><br>They typeOf function returns its TypeRep, which contains its type<br>constructor, but I don&#39;t see how to decide whether that<br>
constructor&#39;s arity is 0 or 1.  If the type has field names<br>I can look at those using Data.Data.conFields and count them,<br>but if it doesn&#39;t I don&#39;t see how to do it.<br><br>-david<br><br>