qualified-id: nested-name-specifier templateopt unqualified-id
nested-name-specifier: :: type-name :: namespace-name :: decltype-specifier :: nested-name-specifier identifier :: nested-name-specifier templateopt simple-template-id ::
The type denoted by a decltype-specifier in a nested-name-specifier shall be a class or enumeration type.
A nested-name-specifier that denotes a class, optionally followed by the keyword template ([temp.names]), and then followed by the name of a member of either that class ([class.mem]) or one of its base classes (Clause [class.derived]), is a qualified-id; [class.qual] describes name lookup for class members that appear in qualified-ids. The result is the member. The type of the result is the type of the member. The result is an lvalue if the member is a static member function or a data member and a prvalue otherwise. [ Note: A class member can be referred to using a qualified-id at any point in its potential scope ([basic.scope.class]). — end note ] Where class-name ::~ class-name is used, the two class-names shall refer to the same class; this notation names the destructor ([class.dtor]). The form ~ decltype-specifier also denotes the destructor, but it shall not be used as the unqualified-id in a qualified-id. [ Note: a typedef-name that names a class is a class-name ([class.name]). — end note ]
The nested-name-specifier :: names the global namespace. A nested-name-specifier that names a namespace ([basic.namespace]), optionally followed by the keyword template ([temp.names]), and then followed by the name of a member of that namespace (or the name of a member of a namespace made visible by a using-directive), is a qualified-id; [namespace.qual] describes name lookup for namespace members that appear in qualified-ids. The result is the member. The type of the result is the type of the member. The result is an lvalue if the member is a function or a variable and a prvalue otherwise.
A nested-name-specifier that denotes an enumeration ([dcl.enum]), followed by the name of an enumerator of that enumeration, is a qualified-id that refers to the enumerator. The result is the enumerator. The type of the result is the type of the enumeration. The result is a prvalue.
In a qualified-id, if the unqualified-id is a conversion-function-id, its conversion-type-id shall denote the same type in both the context in which the entire qualified-id occurs and in the context of the class denoted by the nested-name-specifier.