Is it planned that the offsetof macro will exist in C++,
or do pointers to members replace it somehow?

Thanks,

--Bill
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In article 6rr@blue.usps.gov, Bill Seymour <wseymour@email.usps.gov> writes:
>Is it planned that the offsetof macro will exist in C++,
>or do pointers to members replace it somehow?

The offsetof macro in C++ has defined behavior only if the struct argument
is a "POD" (a C-like struct). In other words, C code using offsetof will
continue to work, but don't use it on C++ classes. Pointer-to-member
is probably what you should be using instead of offsetof.

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Steve Clamage, stephen.clamage@eng.sun.com




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Hi,
Bill Seymour (wseymour@email.usps.gov) wrote:
: Is it planned that the offsetof macro will exist in C++,
: or do pointers to members replace it somehow?

Although it becomes a little bit more trouble, pointers to members
replace it:  The more trouble is due to the fact that you need another
pointer to member type for each type you want to support. However, I
think on PODs the 'offsetof' macro can still be applied. This is e.g
essential when writing Widgets for the X Toolkit in C++.
--
dietmar.kuehl@uni-konstanz.de
http://www.informatik.uni-konstanz.de/~kuehl/
I am a realistic optimist - that's why I appear to be slightly pessimistic
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