[I don't have my C++ spec handy, so...]

Is the following declaration meaningful (and legal)?

    class Foo
    {
        friend class Foo;
        ...
    };

I know that function members of a class already have access to all
of the data members of other objects of the same class type (unlike
other languages such as Eiffel), but does explicitly declaring a
class to be a friend of itself have any harmful effects?

-- David R. Tribble, dtribble@technologist.com --


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On 4 Mar 1999 00:50:17 GMT, David R Tribble <dtribble@technologist.com> wrote:

>Is the following declaration meaningful (and legal)?
>
>    class Foo
>    {
>        friend class Foo;
>        ...
>    };
>
>I know that function members of a class already have access to all
>of the data members of other objects of the same class type (unlike
>other languages such as Eiffel), but does explicitly declaring a
>class to be a friend of itself have any harmful effects?

My compilers give me a warning that the friend declaration has no
effect, so I guess there are no harmful effects.  The warning arises
in template classes.

template <class T>
class Foo
{
   template <class U> friend Foo<U>;
   public:
};

--
----------------------------------
Siemel B. Naran (sbnaran@uiuc.edu)
----------------------------------


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