Article View: comp.std.c++
Article #1394Re: pointer comparisons
From: Jim Adcock
Date: Tue, 05 Jan 1993 00:25
Date: Tue, 05 Jan 1993 00:25
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1668 bytes
In article <1992Dec31.152700.21521@lpi.liant.com> pkt@lpi.liant.com (Scott Turner) writes: |"Same type" is a term used repeatedly in the ARM. It has its limitations, |but is adequate for my purpose. "Defined by use"? How about a "real" definition? |"Point to distinct objects" would imply two things: |(1) Each operand points to one object (not a function, and is not null or | invalid). |(2) The objects are not identicial. I hope to say more about this in | another article. Presumably distinct objects are not identical and objects that are not identical are distinct? ;-) I hope you will tell us more about this later! |The case I'm concerned with is limited to "objects of that type", i.e. |each operand points to a properly constructed object of type A (which may |be a subobject of an enclosing object constructed with a different type). Define "subobject" and "enclosing now." |"Compare not equal" is self-evident; the C standard uses the same kind |of wording. It means that the result of the operator != is 1 (TRUE) and |the result of the operator == is 0 (FALSE). "Compare not equal" was self-evident in C because C has a clearly stated object model with well-defined object identity. No such luck in C++.
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Newsgroups: comp.std.c++ Path: arc1-ca.pugleaf.net!sparky!uunet!microsoft!hexnut!jimad From: jimad@microsoft.com (Jim Adcock) Subject: Re: pointer comparisons Message-ID: <1993Jan05.002547.12038@microsoft.com> Date: 05 Jan 93 00:25:47 GMT Organization: Microsoft Corporation References: <1992Dec27.050118.1628@lpi.liant.com> <1992Dec30.184614.5551@microsoft.com> <1992Dec31.152700.21521@lpi.liant.com> Lines: 29