Re: inheritance headache....

From:

James Kanze <james.kanze@gmail.com>

Newsgroups:

comp.lang.c++

Date:

Sat, 2 Feb 2008 02:20:41 -0800 (PST)

Message-ID:

<ad2b7c2d-b623-4a6d-8dad-3131e06a0e12@s12g2000prg.googlegroups.com>

On Feb 2, 12:35 am, "Alf P. Steinbach" <al...@start.no> wrote:

* James Kanze:

[...]

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

On the contrary, from the original posting:

* b...@blah.com:

Now somewhere, actually EVERYWHERE in this legacy code I see
statements like this;

// semi pseudo with
abstractTarget* createTarget(abstractDescription* desc)
{
// shortcut pseudo code for dynamic cast< > ()
   if ( desc is concreteDesc1)
   {
     return new concreteTarget1();
   }
   else if (desc is concreteDesc2)
   {
     return new concreteTarget2();
   }
   else
   {
     return 0;
   }
}

Notice that no information about the created objects is retained.

Hence, as I figure it, the caller has the responsibility for destroying
them.

In other words, since no information is given, you suppose the
exceptional case, rather than the usual.

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