Re: difference between i++ and ++i in a for loop

From:

James Kanze <james.kanze@gmail.com>

Newsgroups:

comp.lang.c++

Date:

Thu, 19 Feb 2009 02:37:13 -0800 (PST)

Message-ID:

<5f20626a-31d8-49a6-9c27-dd090a8bd4c2@13g2000yql.googlegroups.com>

On Feb 18, 11:56 pm, Alexander Gutenev <gute...@gmail.com> wrote:

On 18 =C6=C5=D7, 01:46, James Kanze <james.ka...@gmail.com> wrote:

Depending on the types involved, and how the compiler
handles them, there may be a difference in performance.
\u0161At least, people keep claiming this; I've done a lot
of measurements, and I've never been able to find any; I
think it's one of those myths that people like to
perpetrate.

For int there would not be any differene, but you can see the
diference on the code like:
for (std::set<int>::iterator i = s.begin(); i != s.end(); ++i);
vs
for (std::set<int>::iterator i = s.begin(); i != s.end(); i++);

I didn't see it when I measured. I measured *all* of the
iterators in the standard library (using the g++
implementations), and found no difference for any of them.

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