Preserving class member-variable order?

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#714

From: Michael
Date: Thu, 07 Aug 2003 23:12

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Hi,

I'm dev'ing in C++ using Codewarrior 8.3, on OS 9.2 & X.

I'm trying to find out if there's a way to preserve the order of class
member variables, ie the order in which they are listed in the class
declaration. I'm hoping to be able to reference a class member indirectly by
deref'ing another class member that is a known distance away. I've done this
before on Windows (VC++) and it works nicely, but the same approach doesn't
seem to work in OS 9 (or maybe because of the CW compiler?). I haven't tried
yet on OS X but I imagine it might be the same on OS 9?

A simple example is below. This simple example might work, but I've been
trying to get it to work in a much larger class. I haven't tested
extensively, thinking that someone might have a quick answer for me.

class MyClass{
    char interestingValue;
    char placeHolder;
}

MyClass obj;

char val = *(&(obj.placeHolder)-1);

I was thinking there might be a compiler option or pragma I could use to fix
the order of the members during compilation. Does anyone have any
suggestions?

Many thanks,
Michael

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From: "Michael" <mstauff@bellatlantic.net>
Newsgroups: comp.sys.mac.programmer.codewarrior,codewarrior.mac
Subject: Preserving class member-variable order?
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