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Date: Mon, 5 Jan 2015 19:12:22 +0100
Cc: PHP Internals <internals@lists.php.net>,
 Dmitry Stogov <dmitry@zend.com>,
 Nikita Popov <nikita.ppv@gmail.com>
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To: Xinchen Hui <laruence@php.net>
Subject: Re: [PHP-DEV] Faster zend sorting implementation
From: dz@heroku.com (David Zuelke)

This sounds reasonable, because given how the sort is *not* stable, =
there will be other cases (totally made up, but let's say ["a", "o", =
"O"]) where the swap does *not* happen. Consistency, and thus a stable =
sort, is better.

But you're saying your patch is "kind of a" stable sorting algo, so is =
it stable only sometimes, or did you mean to say "a kind of"?

David


> On 05.01.2015, at 18:08, Xinchen Hui <laruence@php.net> wrote:
>=20
> Hey:
>=20
>     I was working on zend_qsort improvement. but I got a problem need
> to be disscussed with you fist..
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>     as we know,  previously zend_qsort is not a stable sorting algo.
>=20
>     my draft patch (which already get 0.1% IRs reduce in wordpress)
> is kindof a stable sorting algo, you can find it here
> (https://github.com/laruence/php-src/compare/zend_sort)
>=20
>     so, there is a bc break, like for :
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>     $array =3D array("o",  "O");
>     sort($array, SORT_STRING|SORT_FLAG_CASE);
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>     var_dump($array);
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>     previously implementation does the swap:
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> array(2) {
>  [0]=3D>
>  string(1) "O"
>  [1]=3D>
>  string(1) "o"
> }
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>     but new implementation doesn't not:
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> array(2) {
>  [0]=3D>
>  string(1) "o"
>  [1]=3D>
>  string(1) "O"
> }
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>    do you think such BC break is acceptable? or I still need a RFC? :<
>=20
> thanks
> --=20
> Xinchen Hui
> @Laruence
> http://www.laruence.com/
>=20
> --=20
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>=20