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From: "Rudolf Sykora" <rudolf.sykora@gmail.com>
To: "Fans of the OS Plan 9 from Bell Labs" <9fans@9fans.net>
Subject: Re: [9fans] non greedy regular expressions
Date: Fri, 24 Oct 2008 10:08:29 +0200	[thread overview]
Message-ID: <a560a5d00810240108q62854ec1w16614c90c7071436@mail.gmail.com> (raw)
In-Reply-To: <6988bd18a7bfb3d7def95c11e4dd9bd9@quanstro.net>

> russ has a great writeup on this.
> http://swtch.com/~rsc/regexp/
> i think it covers all your questions.
>
> - erik

I read trough some of that already yesterday. Anyway, am still
puzzled. In the text of

Regular Expression Matching Can Be Simple And Fast
(but is slow in Java, Perl, PHP, Python, Ruby, ...)

R. Cox writes:
---
While writing the text editor sam [6] in the early 1980s, Rob Pike
wrote a new regular expression implementation, which Dave Presotto
extracted into a library that appeared in the Eighth Edition. Pike's
implementation incorporated submatch tracking into an efficient NFA
simulation but, like the rest of the Eighth Edition source, was not
widely distributed.
...
Pike's regular expression implementation, extended to support Unicode,
was made freely available with sam in late 1992, but the particularly
efficient regular expression search algorithm went unnoticed. The code
is now available in many forms: as part of sam, as Plan 9's regular
expression library, or packaged separately for Unix.
---

But any manual page (regexp(6), that of sam)  keeps completely silent
about eg. any submatch tracking.
So what's wrong? Can anybody clarify the situation for me or do I
really have to read the codes?

Ruda



  reply	other threads:[~2008-10-24  8:08 UTC|newest]

Thread overview: 45+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-10-23 18:58 Rudolf Sykora
2008-10-23 19:05 ` erik quanstrom
2008-10-24  8:08   ` Rudolf Sykora [this message]
2008-10-24 12:23     ` erik quanstrom
2008-10-24 16:11       ` Rudolf Sykora
2008-10-24 16:54         ` erik quanstrom
2008-10-24 17:02         ` John Stalker
2008-10-24 17:15           ` Rob Pike
2008-10-24 17:41           ` Rudolf Sykora
2008-10-24 18:01             ` Russ Cox
2008-10-24 19:56               ` Rudolf Sykora
2008-10-24 21:10                 ` Russ Cox
2008-10-24 21:40                   ` Rudolf Sykora
2008-10-24 21:47                     ` erik quanstrom
2008-10-24 22:04                       ` Rudolf Sykora
2008-10-24 22:38                         ` Gabriel Diaz Lopez de la Llave
2008-10-24 22:54                         ` Charles Forsyth
2008-10-24 22:59                           ` Charles Forsyth
2008-10-24 23:52                         ` Tom Simons
2008-10-25 22:35                           ` Rudolf Sykora
2008-10-25 23:02                             ` Steve Simon
2008-10-26  8:57                             ` John Stalker
2008-10-26 18:36                               ` Eris Discordia
2008-10-27  4:55                             ` Russ Cox
2008-10-27  8:28                               ` Rudolf Sykora
2008-10-27 10:18                               ` Charles Forsyth
2008-10-27 13:13                                 ` Eris Discordia
2008-10-27 13:23                                   ` erik quanstrom
2008-10-27 19:42                                     ` Eris Discordia
2008-10-27 16:13                                   ` Brian L. Stuart
2008-11-30  8:29                             ` Yard Ape
2008-12-11 16:32                               ` Rudolf Sykora
2008-10-24 18:02             ` John Stalker
2008-10-24 17:10         ` Uriel
2008-10-24 19:56         ` Charles Forsyth
2008-10-24 19:56           ` Rudolf Sykora
2008-10-26 21:23             ` Rob Pike
2008-10-24 11:27 Aharon Robbins
2008-10-27 19:23 Aharon Robbins
2008-10-27 20:15 ` Eris Discordia
2008-10-27 20:00 Eris Discordia
2008-10-28 14:51 ` Brian L. Stuart
2008-10-28 15:07   ` Eris Discordia
2008-10-27 21:08 Aharon Robbins
2008-10-28 14:53 ` Eris Discordia

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