g++: declaration of a friend from within a namespace

[Alexandre Oliva]

On Jun  2, 2008, Matthias Kaehlcke <matthias@kaehlcke.net> wrote:

> namespace ns { class MyClass { friend MyClass ::operator+(MyClass,
> MyClass); private: int attribute; }; }

This is parsed as MyClass::operator+ (whitespace is not significant),
so you end up missing the return type. 
 
> when removing the default namespace specifier ('::') from the friend
> declaration the error message changes to:

Then the friend declaration injects the name in the enclosing
namespace ns, so that's where you'd have to define it.  A definition
in the global namespace doesn't match, so it isn't granted access to
private members.

> i can't figure out what would be the correct friend declaration with
> the operator in the default namespace.

Adding parentheses around the declarator id (::operator+) should work.

-- 
Alexandre Oliva         http://www.lsd.ic.unicamp.br/~oliva/
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