Re: Why use object pointers rather than objects?

From:

=?UTF-8?B?RXJpayBXaWtzdHLDtm0=?= <Erik-wikstrom@telia.com>

Newsgroups:

comp.lang.c++

Date:

Mon, 15 Oct 2007 23:01:40 GMT

Message-ID:

<ojSQi.11443$ZA.7538@newsb.telia.net>

On 2007-10-16 00:46, Krishna wrote:

On Oct 15, 2:14 pm, Juha Nieminen <nos...@thanks.invalid> wrote:

krishna.kishore.0...@gmail.com wrote:

Why are always object pointers used? (i.e., ObjectType *objPointer)

Always? I don't always use them. In fact, I seldom use them.
This is a very typical example of where I don't use them:

std::string s = "hello";

No pointer there.

one advantage I see is passing them across methods, but is this purely
presentation issue (use 'objPointer' rather than '&obj') or are there
some performance affects?

If you pass an object by value then a copy will most probably be made,
which will often be less efficient than passing by reference or by
pointer. Also there's the slicing problem if inheritance is involved.

Hi Guys,
Thanks for the replies. When I was punching 'always' I was stuck in
the world of GUI, I see pointers being used for GUI objects, 'always'

That would probably be because GUI classes often makes heavy use of
polymorphism, (most graphical elements inherit from a base widget (or
whatever) class, and often implements a number of interfaces).

--
Erik Wikstr??m