Re: Self Assignment check in Copy ctor

From: Risto Lankinen (rlankine_at_hotmail.com)
Date: 02/06/05

  • Next message: Peter Koch Larsen: "Re: Can basic_string<>::c_str() throw exceptions?" 
    Date: 5 Feb 2005 23:37:10 -0800

    > AlgoMan wrote:
    > > Do you need to provide a self assignment check in a copy ctor
    > > (like you provide in an assignment operator).

    Artie Gold <artiegold@austin.rr.com> wrote in message news:<36ktrvF50haq3U1@individual.net>...
    > Two words: What `self'?

    Well, you know, the... the... the 'self':

     - - -

    struct C
    {
       C( const C &r )
       {
          if( this == &r )
          {
             cout << "Hello myself!" << endl;
          }
       }
    };

    int main()
    {
       C c(c);
    }

     - - -

    (Go ahead, try it out if you don't believe it works!)

    > AlgoMan wrote:
    > > If not, why not?

    Because the risk is very very small that somebody would
    accidentally copy-initialize with reference to self. It
    can be done, but the only way to do it is deliberately.

     - Risto -

  • Next message: Peter Koch Larsen: "Re: Can basic_string<>::c_str() throw exceptions?"

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