Re: inheritance headache....

From:

James Kanze <james.kanze@gmail.com>

Newsgroups:

comp.lang.c++

Date:

Fri, 1 Feb 2008 14:42:50 -0800 (PST)

Message-ID:

<732c5480-a61d-4696-8b94-adbaa162f1dc@q77g2000hsh.googlegroups.com>

On Feb 1, 2:12 pm, "Alf P. Steinbach" <al...@start.no> wrote:

* James Kanze:

On Jan 31, 11:12 pm, "Alf P. Steinbach" <al...@start.no> wrote:

* b...@blah.com:

class abstractDescription
{
  AbstractTarget* create(AbstractDescription* desc)
  {
      desc->create();
  }
}

It's clear what you mean, something like

   struct AbstractDescription
   {
       virtual std::auto_ptr<AbstractTarget> create() const = 0;
   };

How is it so clear? Normally, auto_ptr suggests that the caller
will be responsible for deleting the object.

Yes, that was the case.

How do you know? There was nothing in the original posting to
suggest it, and it's rather the exception, and not the rule.

And most of the
time I've seen such a pattern used, this simply isn't the
case---the object registers itself in its constructor for some
sort of external events, and deletes itself when the appropriate
event arises.

And that wasn't the case.

Again, how do you know? It's the more frequent case in well
designed software.

--
James Kanze (GABI Software) email:james.kanze@gmail.com
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