Re: Inheriting from std::vector?

From: Rolf Magnus (ramagnus_at_t-online.de)
Date: 10/25/03

  • Next message: Brett: "Re: How to input 2 inputs in 1 line???" 
    Date: Sat, 25 Oct 2003 14:54:43 +0200

    lilburne wrote:

    >>>>You wrote bad code, having been told it's bad. What's your point?
    >>>>
    >>>
    >>>What was bad about it?
    >>
    >>
    >> You're destroying a non-polymorphic class object polymorphically
    >> (through a pointer to the base class object).
    >>
    >> But you knew that.
    >>
    >> It's illogical to ban usage of a feature just because that feature
    >> _can_ be abused, since almost all language features _can_ be abused,
    >> and I think your use of such an illogical argument was the reason why
    >> Pete plonked you.
    >>
    >
    > It is unlikely that Pete Becker would derive a class from
    > a base that has a non-virtual destructure, without some
    > overriding reason to do so. Because he knows it is a
    > resource leak waiting to happen,

    No, it's not. Polymorphically destroying an object of that class is.
    A knife can be a useful tool, and it isn't evil. Hoever, using it to
    stab people is. Almost everything can be destructive if you want it to
    be.

    > and that safer alternatives are usually available.
    >
    > To pretend that you can ensure that the polymorphic deletion
    > on such a class heirarchy can be avoid just by saying "Don't
    > do it" is ridiculous.

    You could also reinterpret_cast the pointer to char* and delete that
    one. It will also result in improper deletion. But why would anyone do
    such a stupid thing?

    > Certain language features ought to be used with caution, IMO
    > one should learn how to use them properly before you start
    > to abuse them.

    Nope. One should learn how to use them and never abuse them at all.

  • Next message: Brett: "Re: How to input 2 inputs in 1 line???"

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