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Thread: condused with copy construcotrs

  1. #1
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    Default condused with copy construcotrs

    Hi,

    AFAIK, a "default" copy constructor (i.e the one the compiler will implicitly generate if you didn't define your own copy constructor) will copy all non static members using their copy constructors.

    But what do I do, when I have a class that has various parameters that MUST be given at initialization?
    Lets say I have the following class:
    Qt Code:
    1. class myClass(QString port)
    2. {
    3. private:
    4. QString m_port;
    5. //code
    6. };
    To copy to clipboard, switch view to plain text mode 
    now, after initialization, port will be assigned to m_port.
    If I don't define my own copy constructor, then the code:
    Qt Code:
    1. myClass A("ttyS0");
    2. myClass B(A);
    To copy to clipboard, switch view to plain text mode 
    will create class B with m_port == "ttyS0".
    Which is a dangerous thing.

    So my question is:
    Is there a way for me to disable the default copy constructor?
    Defining my own copy constructor is not possible, since I it need to get the port parameter from the user, and each class needs to have its own and different from the others port parameter.

    Thanks.
    EDIT: subject should read "Confused with copy construcotrs
    Last edited by high_flyer; 24th September 2006 at 21:26.

  2. #2
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    Default Re: condused with copy construcotrs

    Quote Originally Posted by high_flyer View Post
    Is there a way for me to disable the default copy constructor?
    Just declare it as private along with operator=().

  3. The following user says thank you to jacek for this useful post:

    high_flyer (24th September 2006)

  4. #3
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    Default Re: condused with copy construcotrs

    Quote Originally Posted by high_flyer View Post
    Is there a way for me to disable the default copy constructor?
    You may declare it as private (and leave unimplemented)..
    J-P Nurmi

  5. The following user says thank you to jpn for this useful post:

    high_flyer (24th September 2006)

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