Re: Why no access specifiers for friends?

From:

"kanze" <kanze@gabi-soft.fr>

Newsgroups:

comp.lang.c++.moderated

Date:

18 Sep 2006 05:27:16 -0400

Message-ID:

<1158563590.309526.83930@e3g2000cwe.googlegroups.com>

Jiang wrote:

As we know the friend declarations introduce the tightest coupling
relationships between a class and its friends, even tighter than
inheritance.

This is strange because the coupling for relationship "is-a" should
be much tighter than relationship "friend-of-a", even in real life.
Why we do not have access specifiers to control the protected
friends or private friends?

I think you're confused by very simplified expressions which
describe the relationship. Inheritance would be more accurately
described by is-an-implementation-of, or
can-be-replaced-in-all-contexts by. Friend, on the otherhand,
means something along the lines of
is-an-intimate-part-of-the-implementation-of.

Maybe I should post this message in comp.std.c++, but I decided
to post it here because this issue is derived from a related thread.
( Sanity check: public/private
http://groups.google.com/group/comp.lang.c++.moderated/browse_frm/thread/f59e8500e81cba2d/786987f601ffd131?hl=en#786987f601ffd131
)

Any comments are welcome.

If there is a change, I'd prefer it to be in the direction of a
type of friendship which allowed access to only certain private
members. In practice, however, I don't think it's worth the
added complexity.

--
James Kanze GABI Software
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