Re: Reference to void

From:
"Greg Herlihy" <greghe@pacbell.net>
Newsgroups:
comp.lang.c++.moderated
Date:
3 Nov 2006 15:16:01 -0500
Message-ID:
<1162578184.584838.6480@f16g2000cwb.googlegroups.com>
Seungbeom Kim wrote:

Francis Glassborow wrote:
I agree that when people use the term 'const reference' it can mean only
one thing, but I think such usage should be discouraged, to keep the
analogy among references, pointers, and iterators. (So, "be strict in
what you say, and lenient in what you accept." :)) Why add the confusion
to just save one word; things are most clearly described when there's no
exception and everything can be described in a uniform way.


Such uniformity is misleading - because it creates the false impression
that name of a reference is analogous to the name of pointer. When the
reality is the names are used in opposite ways:

For example:

      int * const p;

"p" names the const pointer object and not the object that it may be
pointing to (and which is not named in this declaration). With
reference declarations, the situation is just the opposite:

      int& ref = i;

"ref" names the object being referenced ("a reference may be thought of
as the name of an object") and the there is no, other referencing
object. So ref is not a "reference to an int" as much as ref is "the
int being refererced" in this expression.

If we stop thinking of references as some kind of hidden pointer we have
a better chance of not confusing terminology used for speaking/writing
about references with that used for pointers.


Even without thinking of references as some kind of hidden pointers (in
implementation details), we already have the analogy and similarities
among references, pointers, and iterators on a higher level, and I don't
see why that adds the confusion. What makes references distinct in this
problem is just that they are not objects and they cannot be const.


The name of a reference names an object (and therefore the name can be
used in the program just like an object). So at the very least "a
reference to const" and a "const reference" are synonymous - because
the object being refererced is none other than the object being named.
A "const reference" however is the more accurate (and should be the
preferred) term since the name is not so much referring to an object,
as much as it is an object that is being referred to.

Greg

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