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- From: fjh@mundook.cs.mu.OZ.AU (Fergus Henderson)
- Message-ID: <4k8g95$jcq@mulga.cs.mu.OZ.AU>
- X-Original-Date: 7 Apr 1996 13:34:29 GMT
- Path: in1.uu.net!bounce-back
- Date: 08 Apr 96 09:03:00 GMT
- Approved: fjh@cs.mu.oz.au
- Newsgroups: comp.std.c++
- Subject: Re: dynamic_cast<void*>
- Organization: Comp Sci, University of Melbourne
- References: <4k1a4r$dim@rznews.rrze.uni-erlangen.de>
- X-Auth: PGPMoose V1.1 PGP comp.std.c++
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- =cNU/
-
- anhaeupl@late.e-technik.uni-erlangen.de (Bernd Anhaeupl) writes:
-
- >Section 5.2.6 paragraph 7 of the April 95 WP states, that for
- >polymorphic types, the result of a dynamic_cast<void*>(v) "is a
- >pointer to the complete object (12.6.2) pointed to by v". Now
- >section 12.6.2 does not define the term "complete object", which
- >actually happens in section 1.4 paragraph 2, but the term
- >"most derived class". This makes a differnce, if we pass a pointer
- >to a data member subobject (and not a base class subobject) to
- >dynamic_cast. According to 12.6.2, we would get the address of that
- >data member, according to 1.4, the address of the containing
- >object of that data member.
- >
- >Please note, that the term "complete object (12.6.2)" is also used
- >in section 5.2.7, where the typeid expression is defined. Therefore
- >I suppose, that in 5.2.6 and 5.2.7 "most derived object" is meant
- >instead of "complete object" in both sections. Is this correct?
-
- Yes.
-
- The term "complete object" was used to mean two different things
- by different members of the C++ committee; one of those meanings
- is what is now called "most derived object".
-
- This error has been corrected in the Jan 96 draft, both in 5.2.6
- and in 5.2.7.
-
- --
- Fergus Henderson <fjh@cs.mu.oz.au> | "I have always known that the pursuit
- WWW: <http://www.cs.mu.oz.au/~fjh> | of excellence is a lethal habit"
- PGP: finger fjh@128.250.37.3 | -- the last words of T. S. Garp.
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