Re: Conversion operators and private inheritance

From:

Nikolay Ivchenkov <tsoae@mail.ru>

Newsgroups:

comp.lang.c++.moderated

Date:

Sun, 7 Feb 2010 17:01:14 CST

Message-ID:

<68a4dfec-ed6e-4c04-b5ee-07f287119223@a32g2000yqm.googlegroups.com>

On 1 Feb, 16:57, Daniel Kr?gler <daniel.krueg...@googlemail.com>
wrote:

"A conversion function is never used to convert a (possibly
cv-qualified) object to the (possibly cv-qualified) same object
type (or a reference to it), to a (possibly cv-qualified) base
class of that type (or a reference to it), or to (possibly
cv-qualified) void.[Foot note 111]

111) These conversions are considered as standard
conversions for the purposes of overload resolution
(13.3.3.1, 13.3.3.1.4) and therefore initialization (8.5)
and explicit casts (5.2.9).

I think, the footnote 111 is incorrect.

   struct X
   {
       operator X &() { return *this; }
   };

   int main()
   {
       X &x = X();
   }

See 13.3.3.1.4/3: "A standard conversion sequence cannot be formed if
it requires binding an lvalue reference to non-const to an rvalue
(except when binding an implicit object parameter; see the special
rules for that case in 13.3.1)."

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