Title
using-declarations and cv-qualifiers
Status
cd1
Section
9.9 [namespace.udecl]
Submitter
Liam Fitzpatrick

Created on 2000-11-02.00:00:00 last changed 161 months ago

Messages

Date: 2003-04-15.00:00:00

[Voted into WP at April 2003 meeting.]

Date: 2002-04-15.00:00:00

Proposed resolution (04/02):

In 9.9 [namespace.udecl] paragraph 12 change:

When a using-declaration brings names from a base class into a derived class scope, member functions in the derived class override and/or hide member functions with the same name and parameter types in a base class (rather than conflicting).
to read:
When a using-declaration brings names from a base class into a derived class scope, member functions and member function templates in the derived class override and/or hide member functions and member function templates with the same name, parameter-type-list (9.3.4.6 [dcl.fct]), and cv-qualification in a base class (rather than conflicting).

In 11.7.3 [class.virtual] paragraph 2 change:

If a virtual member function vf is declared in a class Base and in a class Derived, derived directly or indirectly from Base, a member function vf with the same name and same parameter list as Base::vf is declared, then Derived::vf is also virtual (whether or not it is so declared) and it overrides Base::vf.
to read:
If a virtual member function vf is declared in a class Base and in a class Derived, derived directly or indirectly from Base, a member function vf with the same name, parameter-type-list (9.3.4.6 [dcl.fct]), and cv-qualification as Base::vf is declared, then Derived::vf is also virtual (whether or not it is so declared) and it overrides Base::vf.

See issue 140 for the definition of parameter-type-list.

Date: 2001-04-15.00:00:00

Notes on the 04/01 meeting:

The hiding and overriding should be on the basis of the function signature, which includes any cv-qualification on the function.

Date: 2004-09-10.00:00:00

According to 9.9 [namespace.udecl] paragraph 12,

When a using-declaration brings names from a base class into a derived class scope, member functions in the derived class override and/or hide member functions with the same name and parameter types in a base class (rather than conflicting).

Note that this description says nothing about the cv-qualification of the hiding and hidden member functions. This means, for instance, that a non-const member function in the derived class hides a const member function with the same name and parameter types instead of overloading it in the derived class scope. For example,

    struct A {
      virtual int f() const;
      virtual int f();
    };
    struct B: A {
      B();
      int f();
      using A::f;
    };

    const B cb;
    int i = cb.f(); // ill-formed: A::f() const hidden in B

The same terminology is used in 11.7.3 [class.virtual] paragraph 2:

If a virtual member function vf is declared in a class Base and in a class Derived, derived directly or indirectly from Base, a member function vf with the same name and same parameter list as Base::vf is declared, then Derived::vf is also virtual (whether or not it is so declared) and it overrides Base::vf.
History
Date User Action Args
2008-10-05 00:00:00adminsetstatus: wp -> cd1
2003-04-25 00:00:00adminsetmessages: + msg863
2003-04-25 00:00:00adminsetstatus: ready -> wp
2002-11-08 00:00:00adminsetstatus: review -> ready
2001-11-09 00:00:00adminsetmessages: + msg552
2001-11-09 00:00:00adminsetstatus: drafting -> review
2001-05-20 00:00:00adminsetmessages: + msg493
2001-05-20 00:00:00adminsetstatus: open -> drafting
2000-11-02 00:00:00admincreate