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From: Drew Adams <drew.adams@oracle.com>
To: Marcin Borkowski <mbork@mbork.pl>,
	Stefan Monnier <monnier@iro.umontreal.ca>
Cc: "help-gnu-emacs@gnu.org" <help-gnu-emacs@gnu.org>
Subject: RE: [External] : Re: Performance of `re-search-backward' vs `re-search-forward'
Date: Mon, 12 Apr 2021 20:40:36 +0000	[thread overview]
Message-ID: <SA2PR10MB4474587E68403400BF0EBE10F3709@SA2PR10MB4474.namprd10.prod.outlook.com> (raw)
In-Reply-To: <8735vvb8c5.fsf@mbork.pl>

> So both basically move character by character and check if the regex
> matches there (more or less)?

They don't move character by character.
They use the Boyer-Moore search algorithm.

https://en.wikipedia.org/wiki/Boyer%E2%80%93Moore_string-search_algorithm



  reply	other threads:[~2021-04-12 20:40 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-12  5:38 Performance of `re-search-backward' vs `re-search-forward' Marcin Borkowski
2021-04-12 15:13 ` Stefan Monnier
2021-04-12 19:39   ` Marcin Borkowski
2021-04-12 20:40     ` Drew Adams [this message]
2021-04-12 21:03       ` [External] : " Stefan Monnier
2021-04-12 20:59     ` Stefan Monnier
2021-04-13  6:07       ` Marcin Borkowski

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