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From: Pete Becker<pete@versatilecoding.com>
Newsgroups: comp.std.c++
Subject: Re: Typo in the Working Draft of the C++ Standard # 3337
Date: Wed, 18 Apr 2012 08:54:34 -0700 (PDT)
Organization: Roundhouse Consulting, Ltd.
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Xref: csiph.com comp.std.c++:481

On 2012-04-18 06:11:23 +0000, Vlad from Moscow said:

>  I found a typo in the Working Draft of the C++ Standard #3337 in
>  paragraph #2 of the section 11.3 Friends. There is the following
>  example
>
>  [ Example:
>  class A {
>  class B { };
>  friend class X;
>  };
>  struct X : A::B { // OK: A::B accessible to friend
>  A::B mx; // OK: A::B accessible to member of friend
>  class Y {
>  A::B my; // OK: A::B accessible to nested member of friend
>  };
>  };
>  —end example ]
>
>  It is obvious that instaed of struct X : A::B shall be class X : A::B
>  because the friend declaration of X uses specifier class.
>  Maybe this typo is present in the C++ Standard. It should be checked.

It's the same in the standard. Probably should be changed, for clarity.
But my recollection is (I haven't looked it up) that struct, class, and
even union can be used interchangeably in a forward declaration; it's
only at the point of definition that the keyword matters.

-- 
  Pete
Roundhouse Consulting, Ltd. (www.versatilecoding.com) Author of "The
Standard C++ Library Extensions: a Tutorial and Reference
(www.petebecker.com/tr1book)


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