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Date: Wed, 20 Mar 2019 11:26:12 -0400
Message-ID: <CAK5kH3ynfkLii-t7A_kATD00G+7Xser+55nsz8K=BAGo6YnwJQ@mail.gmail.com>
To: Nikita Popov <nikita.ppv@gmail.com>
Cc: PHP internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] PCRE partial matching
From: cananian@wikimedia.org ("C. Scott Ananian")

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Looks nice to me.  In connection with the PREG_LENGTH_CAPTURE option
floated in a previous post, this would easily let the wikimedia/remex-html
package parse HTML in a streaming fashion; it would fill up a buffer array
and then do an incremental parse, stopping as soon as a (hard) partial
match was found, then move the prefix returned to the start of the buffer,
wait for the buffer to fill more, then restart.
 --scott

On Wed, Mar 20, 2019 at 5:32 AM Nikita Popov <nikita.ppv@gmail.com> wrote:

> Hi internals,
>
> PCRE has some very nice partial matching functionality described at
> https://www.pcre.org/current/doc/html/pcre2partial.html. This is useful
> for
> streaming processing, as it allows you to distinguish between "there's
> definitely no match here" and "this could match starting from position N,
> but we need more data to find out".
>
> Here is a PR to expose this functionality from PHP:
> https://github.com/php/php-src/pull/3969 The PR has a basic description of
> the API.
>
> What do you think?
>
> Nikita
>


-- 
(http://cscott.net)

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