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References: <6E76B52E-7543-4F09-A948-A7910513B548@gmail.com>
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Date: Tue, 16 Mar 2010 23:28:47 +0100
Message-ID: <7f3ed2c31003161528m4a31845fjefd4a7696baaab51@mail.gmail.com>
To: Mikko Koppanen <mkoppanen@php.net>
Cc: Christian Schneider <cschneid@cschneid.com>, Felix De Vliegher <felix.devliegher@gmail.com>, 
	PHP internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] Re: array_seek function
From: hannes.magnusson@gmail.com (Hannes Magnusson)

On Tue, Mar 16, 2010 at 17:12, Mikko Koppanen <mkoppanen@php.net> wrote:
> On Tue, Mar 16, 2010 at 2:12 PM, Christian Schneider
> <cschneid@cschneid.com> wrote
>> I thinks the user space implementation
>>
>> function array_seek($array, $pos)
>> {
>> =A0 =A0 =A0 =A0$a =3D array_values($array);
>> =A0 =A0 =A0 =A0return $a[$pos];
>> }
>>
>> is simple enough to not add a native function for this.
>>
>> It might not be the most efficient way to do it but I doubt that it is
>> something done frequently enough to justify another native function.

> slightly modified version of the original patch
> http://valokuva.org/~mikko/array_seek.patch.txt. The difference to the

I once porpoised similar patch to in_array, where it didn't reset the
position after finding the "found element".


In applications like PhD, this is extremely useful and safes us at
least 10% overhead (at the time I benchmarked it with my patch to
in_array()).

I think we wound up with something like:
while (list($key, $val) =3D each($array)) {
  if ($key =3D=3D "foobar") {
    break;
  }
}
next($array);
$current_index =3D current($array);
To get the _next_ value after the known "currently known value (or key)".

In an application like PhD (which already brought 24hours (DSSSL
24hours, xsltproc two formats compile time to) down to ~3-4minutes
(3-5formats), 10% of _language_ overhead is extremely important, so I
am all for a function that can do this (our/my goal is max 1minute...
- sorry, HD read/write is still extremely expensive :(, it simply cant
get faster then that afaict - if you have an idea; GSOC is open for
experiments.. :D).

-Hannes