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From: duvarney@yoyodyne.rtp.dg.com (Dan DuVarney)
Newsgroups: comp.lang.c++
Subject: Re: Is there a way to tell which derived class an object belongs to?
Message-ID: <2930@xyzzy.UUCP>
Date: 5 Feb 90 04:41:33 GMT
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Reply-To: duvarney@yoyodyne.rtp.dg.com (Dan DuVarney)
Organization: Data General Corporation, Research Triangle Park, NC
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If you are interested in telling which derived class an object belongs to, 
then you should check out Keith Gorlen's OOPS library.

OOPS defines a class "Class" which contains the name, inheritance, etc. for a 
given class. For each OOPS class, there is a corresponding member of Class,
usually called "class_<class-name>."

There is a virtual function "isA()" for each object that returns a 
reference to the appropriate Class variable. This scheme is more complicated 
than type-id numbers, but has the advantage that you can ask questions like 
"is this object a member of a class derived from the class 'Set?'"

Dan DuVarney      ...!mcnc!rti!dg-rtp!duvarney