Thread: Destructor as a virtual

  1. 06-01-2011 #1
    Samson144
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    Question Destructor as a virtual

    hi.
    How do you is it illegal to define virtual destructors?
  2. 06-01-2011 #2
    kmdv
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    It is legal.
    Code:
    virtual ~destr();
    http://kmedwecki.com/
  3. 06-01-2011 #3
    Samson144
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    thanks and what about constructors?
  4. 06-01-2011 #4
    laserlight
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    Not only it is legal, but it is good practice to declare the destructor of a polymorphic base class as virtual so as to avoid undefined behaviour should an object of a derived class be destroyed through a base class pointer.

    Quote Originally Posted by Samson144
    what about constructors?
    You cannot declare constructors as virtual, but read this FAQ: What is a "virtual constructor"?
    Quote Originally Posted by Bjarne Stroustrup (2000-10-14)
    I get maybe two dozen requests for help with some sort of programming or design problem every day. Most have more sense than to send me hundreds of lines of code. If they do, I ask them to find the smallest example that exhibits the problem and send me that. Mostly, they then find the error themselves. "Finding the smallest program that demonstrates the error" is a powerful debugging tool.
    Look up a C++ Reference and learn How To Ask Questions The Smart Way
  5. 06-01-2011 #5
    Samson144
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    thanks thanks thanks
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