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Re: undefined reference to vtable

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On 07/16/11 11:05 AM, eric wrote:
> Dear Advanced C/g++ programers:
>
> a simple program about Creating an interface with an Abstract Base
> Class. from book (C++ cookbook) page 308, 309. Example 8-11. using a
> pure interface.
> ----------------------
> // Example 8-11 Using a pure interface
> class Person {
> public:
> virtual void eat() = 0;
> virtual void sleep() = 0;
> virtual void walk() = 0;
> virtual void jump() = 0;
> };
>
> class IAirbone {
> public:
> virtual void fly() = 0;
> virtual void up() = 0;
> virtual void down() = 0;
> };
>
> class Superhero : public Person, // A superhero *is* a person
> public IAirbone { // and flies
> public:
> virtual void eat();
> virtual void sleep();
> virtual void walk();
> virtual void jump();
> virtual void fly();
> virtual void up();
> virtual void down();

None of the above need the "virtual" key word.

> virtual ~Superhero();

Why have you given this a virtual destructor?

<snip>

> --------------------------------------------------
> actually that book even did not specially define Superhero::walk(),
> that is
> I add by myself to escape my compile's error(is that right? or book's
> is right?)

They must be defined.

-- 
Ian Collins

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undefined reference to vtable eric <cneric12lin0@gmail.com> - 2011-07-15 16:05 -0700
  Re: undefined reference to vtable Ian Collins <ian-news@hotmail.com> - 2011-07-16 11:35 +1200
  Re: undefined reference to vtable Arvind <bharti.arvind@gmail.com> - 2011-07-15 20:49 -0700

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