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Can pure virtual function be called in base class constructor?

Hi,

A pure function is called in the base function constructor. It generate
a run time error: "pure virtual method called".

My problem is that class A have some derived classes. I want A's
constructor change its behaviour accounting to the derived class.

I tried to make A::fun() not pure virtual but virtual. It doesn't
generate any error. But A::fun() is called in A's construction, while I
want B::fun() be called. I just don't want to define a default virtual
function.

I'm wondering if there is any work around to solve this problem.

Best wishes,
Peng
#include <iostream>

class A{
public:
A(){ fun();}
virtual void fun() = 0;
};

class B : public A{
public:
virtual void fun(){
std::cout << __PRETTY_FUNCTI ON__ << std::endl;
}
};

int main(int argc, char *argv[])
{
B b;
}

Oct 14 '05
10 2990
In message <43************ ***@news.indivi dual.net>, Alf P. Steinbach
<al***@start.no > writes
* Richard Herring:
... or point to the wrong FAQ ;-(


The FAQ numbering changed after my posting. Don't be such a whiner. ;-)

OK, I'll leave that to everyone you've contradicted in this thread ;-)

--
Richard Herring
Oct 18 '05 #11

This thread has been closed and replies have been disabled. Please start a new discussion.

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