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Subject: [boost] [bind] virtual function pointer woes
From: Eric Niebler (eric_at_[hidden])
Date: 2009-01-08 14:19:04

Imagine I have a base class B with a virtual function f() that is
overridden in a derived class D ...

struct B { virtual void f() { std::printf("B\n"); } };
struct D : B { virtual void f() { std::printf("D\n"); } };

Now, I can have a derived object D and call the base member directly
using qualification:

D d;
d.B::f(); // OK, called B::f

But if I take the address of B::f for use with boost::bind, I get a
thunk that always uses virtual dispatch...

boost::bind( &B::f, _1 )( d ); // Hrm, calls D::f

What if I don't want the virtual dispatch, and I really want this to
behave like d.B::f()?

I know this is not specifically a problem with boost::bind, but a more
general property of (virtual) member function pointers. Is there any way
to get a non-virtual member function pointer to a virtual member
function? If there is a way, I'm sure I don't know it.

Eric Niebler
BoostPro Computing

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