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sizeof(Struct:: Member) rationale

Hello All,

I confronted recently with the fact that the size of a struct member
can't be determined with sizeof(Struct:: Member). I'm aware of the
alternative methods to do this, however, I'm interested in the
rationale why the Struct::Member syntax is disallowed.

Thanks, P
Sep 2 '08 #1
5 1770
petschy wrote:
Hello All,

I confronted recently with the fact that the size of a struct member
can't be determined with sizeof(Struct:: Member). I'm aware of the
alternative methods to do this, however, I'm interested in the
rationale why the Struct::Member syntax is disallowed.
Was it even proposed?

If so, what benefits would it bring?

--
Ian Collins.
Sep 2 '08 #2
Was it even proposed?

I don't know.
If so, what benefits would it bring?
I needed the size of a member, without an actual instance and the
syntax 'felt' natural. This could be done, so I just wondered why is
it disallowed.

P
Sep 2 '08 #3
petschy wrote:
I confronted recently with the fact that the size of a struct member
can't be determined with sizeof(Struct:: Member). I'm aware of the
alternative methods to do this, however, I'm interested in the
rationale why the Struct::Member syntax is disallowed.
AFAIK, it will be allowed in the next standard.
Sep 2 '08 #4
On 2 Sep, 22:42, petschy <pets...@gmail. comwrote:
Hello All,

I confronted recently with the fact that the size of a struct member
can't be determined with sizeof(Struct:: Member). I'm aware of the
alternative methods to do this, however, I'm interested in the
rationale why the Struct::Member syntax is disallowed.

Thanks, P
Hi. As Juha pointed out, this is already in the draft for the next
standard, but that does not really answer your question :).

You may find these links interesting:

http://www.open-std.org/JTC1/sc22/wg...fects.html#198
http://www.open-std.org/jtc1/sc22/wg...007/n2253.html

DP
Sep 3 '08 #5

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