Re: Instantiation of virtual member functions of class templates

From:

Michael <mcmccarty@gmail.com>

Newsgroups:

comp.lang.c++.moderated

Date:

Sat, 22 Jan 2011 08:24:27 CST

Message-ID:

<05fd8a73-42a2-404a-9d92-32090a424c66@s5g2000yqm.googlegroups.com>

On Jan 21, 8:54 pm, Nikolay Ivchenkov <ts...@mail.ru> wrote:

Given the following example:

        #include <iostream>

        struct B
        {
                virtual void f() const = 0;
        };

        template <class T>
                struct D : B
        {
                // overrides B::f
                virtual void f() const
                {
                        T()();
                }
        };

        struct F
        {
                void operator ()() const
                {
                        std::cout << "F::operator()\n";
                }
        };

        int main()
        {
                D<F> d;
                B &b = d;
                b.f(); // statically refers to B::f
                       // dynamically calls D<F>::f
        }

is there normative rules that require D<F>::f to be implicitly
instantiated?

I'm guessing that the rules regarding the population of D<F>'s virtual
table would do the trick.

Mike

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