🚀 go-pugleaf

In article 1rp@fsuj01.rz.uni-jena.de,  mkt@isun04.inf.uni-jena.de (Tilo Koerbs) writes:

>	class X;

>	class Y {
>		class X {};
>		friend class ::X;  // error!!!
>	};

No, that example is OK.

>I watched the ARM and found out:
>	Section 11.4: "... All the functions of a class X can be
>		made friends of a class Y by a single declaration
>		using an 'elaborated-type-specifier' ('9.1):

>			class Y {
>				friend class X;
>				// ...
>			};"

>	'elaborated-type-specifier':
>		'class-key' 'class-name'
>		'class-key' 'identifier'
>		enum 'enum-name'

>	'class-key':
>		class
>		struct
>		union

>	'class-name':
>		'identifier'

The grammar in the ARM is not quite complete or correct. The draft standard says

	elaborated-type-specifier:
		class-key  ::[opt]  nested-name-specifier[opt] identifier
		enum  ::[opt]  nested-name-specifier[opt] identifier

So things like
	friend class ::X;
	friend class A::B::X;
are allowed by the syntax.

---
Steve Clamage, stephen.clamage@eng.sun.com


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