Re: 'const' usage

From:
"Alf P. Steinbach" <alfps@start.no>
Newsgroups:
microsoft.public.vc.language
Date:
Wed, 21 May 2008 02:46:13 +0200
Message-ID:
<oeGdnc3HsNXB7a7VnZ2dnUVZ_rDinZ2d@comnet>
* lost_in_space:

"Vladimir Grigoriev" <vlad.moscow@mail.ru> wrote in message
news:efyMr2muIHA.2292@TK2MSFTNGP05.phx.gbl...

"Giovanni Dicanio" <giovanni.dicanio@invalid.com> wrote in message
news:eAhXknbuIHA.5580@TK2MSFTNGP04.phx.gbl...

It is not weired.
In fact, you can have a const method that returns a non-const object,
e.g.

SomeObject * SomeFactory::BuildSomeObject() const
{
   ...
   return new SomeObject(...);
}

The caller can modify SomeObject instance (returned by pointer); but the
BuildSomeObject method (of class SomeFactory) does not modify the
internal status of SomeFactory instance.

It is more weired if three const qualifiers are present. :)

const SomeObject * const SomeFactory::BuildSomeObject() const;

 >
 > I understand what the first and third are doing; what effect does the second
 > have?

None, because rvalues of built-in types are effectively const already.

Cheers, & hth.,

- Alf

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