slotp

[David J. Marchette <marchett%cod@nosc.ARPA>]

Is there an easy way to tell if an instance variable (or slot) is
available in a particular structure?  Given an instance of a structure,
I'd like an easy way to tell if location is one of its instance variables
(or slots). One way would be to inspect the plist of the instances 
structure:  (I don't have a machine available at the moment, but you
get the idea)

(member 'location (symbol-plist (type-of foobar)))

...or whatever.  Is there an easier way, assuming that something like
the above would even work?  I think something like it would work on the
Symbolics, but I don't know if it would be portable.  A predefined function 
slotp would be nice, but such does not seem to be available. 

Thanks for any help.

dave

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* David Marchette                 *
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