Re: Is there any problem with customizing a new interface out of other interfaces?

From:

"Alf P. Steinbach /Usenet" <alf.p.steinbach+usenet@gmail.com>

Newsgroups:

comp.lang.c++

Date:

Thu, 02 Sep 2010 10:12:24 +0200

Message-ID:

<i5nm9e$pks$1@news.eternal-september.org>

* Vladimir Jovic, on 02.09.2010 09:34:

red floyd wrote:

On Sep 1, 2:14 am, Goran Pusic <gor...@cse-semaphore.com> wrote:

On Aug 31, 9:31 pm, DeMarcus <use_my_alias_h...@hotmail.com> wrote:

class ICloner
{
public:
virtual ~ICloner() {}
virtual ICloner* clone() = 0;
};

P.S. shouldn't ICloner::Clone return something else (some common base
class), not the ICloner? (That's what non-C++ frameworks that
implement "cloneable" interface are doing...)

Such as what? There is *no* common base class. And by using
covariant
return, ICloner is fine.

e.g. the following is perfectly cromulent:

class Cloneable : public ICloner {
public
Cloneable* clone() { return new Cloneable(*this); }
};

Shouldn't that be like this :

class Cloneable : public ICloner {
public
virtual ICloner* clone() { return new Cloneable( *this ); }
};

?

No.

On the other hand, the method should be 'const'.

And on the third hand, an interface like ICloner serves no practical purpose.

Cheers & hth.,

- Alf

--
blog at <url: http://alfps.wordpress.com>