Re: [Phpgroupware-developers] i++ versus ++i

[Chris Weiss]

So I did a benchmark, 100 iteration of 100,000 increments and averaged them.
The pre-increment is .004 seconds faster on average on P4 2.24Ghz using php
4.3.1 CLI that comes with Mandrake 9.1.

So there's about a 40 nanosecond difference between the two with ++$i being
faster.

http://cw.darktech.org/cw/test.phps

You might also be interested to know that if I didn't preload $i to 100000 in
a loop first it adds .003 seconds to the first loop.

Chris Weiss (address@hidden) wrote:
>
> http://www.faqts.com/knowledge_base/view.phtml/aid/1/fid/40
> "echo is marginally faster since it doesn't set a return
> value if you really want to get down to the nitty gritty."
>
> I don't see any mention of speed difference in
> http://us2.php.net/language.operators.increment.  If there are really found to
> be the data should be posted there.  It's quite possible though that will be
> no difference.  Where is compiled the temp var is needed, but sine php is
> interpreted it's possible that internanly there is a temp var in both cases.
>
>
> Joseph Engo (address@hidden) wrote:
> >
> > -----BEGIN PGP SIGNED MESSAGE-----
> > Hash: SHA1
> >
> > Well, first off that page is for C++.  I am not sure if the same
> > applys to PHP or not.  It would be interesting to research.
> >
> > This is the first I am hearing about echo vs print.  Honestly, what
> > are the differences if any ?  I have personally used echo since I
> > started in PHP.  Why ?  I don't know, I guess to be different from the
> > other languages I use.
> >
> > Joseph Engo
> >
> > Chris Weiss wrote:
> >
> > |noted.  IMO not worth chnaging old code unless you're redoing that area
> > |anyway.  It's very a minimal cost (kind of like echo vs print) and
> > changing it
> > |any places where it's used inline will intruduce bugs.
> > |
> > |Kai Hofmann (address@hidden) wrote:
> > |
> > |>Just for info, why it is better to use ++$i instead of $i++
> > |>
> > |>source: http://www.gotw.ca/gotw/002.htm
> > |>
> > |>Preincrement is more efficient than postincrement, because for
> > postincrement
> > |>the object must increment itself and then return a temporary
> > containing its
> > |>old value. Note that this is true even for builtins like int!
> > |>
> > |>[Guideline] Prefer preincrement, avoid postincrement.
> > |>
> > |>
> > |>
> > |>Have a happy weekend.
> > |>
> > |>  Kai/PowerStat
> > |>
> > |>--
> > |>*****    Open Source und Linux im professionellen Einsatz    *****
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> > |>Dipl.-Inform. Kai Hofmann                    Team Softwarelösungen
> > |>pro|business AG, EXPO Plaza 1 (Deutscher Pavillon), 30539 Hannover
> > |>E-Mail: address@hidden,   Tel.: 0511/60066-332, Fax: -355
> > |>WWW: http://www.probusiness.de/
> > |>
> > |>
> > |>
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