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	Boolean Regexes - perl6:
		Looking deeper into the handling of advanced regexs, there are potential needs for many other concepts, to allow a regex to extract information directly from a complex file in one go, rather than a mixture of splits and nested regexes as is typically needed today.
		Within a complex boolean regex there are likely to be lots and lots of brackets to nest and control the behaviour of the regex.
		Rather than having to sprinkle the regex with (?:) line noise, it would be nicer to just use ordinary brackets () and only support capturing of elements by using one of the (?$=) or (?%=) constructs that have been proposed elsewhere (RFC 112 and RFC 150).
	dev.perl.org /rfc/198.html (1080 words)

	Book Review: Mastering Regular Expressions
		Regexes are very compact and powerful, but that compactness also leads many people to complain that they're difficult to understand after you've written them.
		Regexes are combinations of /, \, ^, $, (, and many other punctuation characters, along with ordinary letters and numbers.
		I have been using regexes for years, and I was surprised, not so much by the advanced features that I mostly knew were there and just hadn't had the need to learn yet, but actually by the gotchas that exist even in simple expressions.
	tejasconsulting.com /DFWUUG/regex.html (870 words)

	Regular expression - Wikipedia, the free encyclopedia
		A regular expression (abbreviated as regexp, regex, or regxp, with plural forms regexps, regexes, or regexen) is a string that describes or matches a set of strings, according to certain syntax rules.
		Regular expressions are used by many text editors and utilities to search and manipulate bodies of text based on certain patterns.
		Perl regular expressions were derived from regex written by Henry Spencer.
	en.wikipedia.org /wiki/Regular_expression (2995 words)

	Regular Expression Security: Don’t Accept Arbitrary Regexes (Lenny Domnitser’s domnit.org)
		Modern regexes, as used in programming, are not really regular expressions, according to the mathematical definition.
		Modern regexes, when using some of their more powerful features, do not necessarily correspond to these machines, and can be very slow.
		Accepting arbitrary regexes is to be considered dangerous unless care is taken to fully understand and implement a safe solution.
	domnit.org /2007/03/regex (754 words)

	DevPapers - article Regexes
		We also learned what regexes were and why we'd use these in our every scripts.
		Regular Expressions are a huge topic all on it's own, there is no possible way to go over all of them here so you may wish to purchase a book on the topic (yes, complete books are dedicated to these) for future reading and understanding.
		One of the most useful, in my opinion of course, special characters in regexes is the.
	www.devpapers.com /article/281 (1483 words)

	ShowUsYour<Regex> : Is RegExLib full of "it"?
		I have written regexes of each type mentioned above and their usefullness or lack of is not always as staightfoward as people seem to want them be.
		I agree that email validation with a regex is not a good idea in general because it is impossible to write a regex that is 100% compliant with RFC 2822 but if you are only working with a subset of mailboxes it may be a viable option.
		Of course the date regex might not be accurate in a universal sense, but that does not mean it could never have application.
	regexadvice.com /blogs/dneimke/archive/2005/04/01/259.aspx (1856 words)

	[Lvlug] Idea for Regexes
		Each element of a regex is matched against the > > > text.
		Where one consisting of a variable amount of characters is found > > > to not match, a user-specified number of characters can be skipped over, > > > and then started again with the next element.
		Regexes do > > > not otherwise take misspellings and alternative spellings, etc. into > > > account.
	www.thelinuxlink.net /pipermail/lvlug/2004-June/010843.html (618 words)

	Short introduction to regular expressions — EOGEO (Site not responding. Last check: 2007-11-03)
		Regular expressions, or regexes help writing powerful searches, search and replaces, and they also can be used to split text-based input into meaningful chunks.
		While regular expressions are often quite portable, i.e., one may be able to use Perl regexes in Java with some Java regex library, that is not to be trusted.
		Regexes are good for looking out for interesting things in an input stream.
	eogeo.org /Projects/projects_wiki/ShortIntroductionToRegularExpressions (1538 words)

	Is there something more efficient than regexes for parsing data?
		Regexes work fine, but there are instances that I get back 10,000 results.
		I know that in general, string functions are faster than regexes.
		Any suggestions other than regex or string functions) would be greatly appreciated.
	forums.devshed.com /t70260/s.html (548 words)

	Regular expression -- Facts, Info, and Encyclopedia article (Site not responding. Last check: 2007-11-03)
		Perl regular expressions were derived from (Click link for more info and facts about regex) regex written by (Click link for more info and facts about Henry Spencer) Henry Spencer.
		Although still named "regular expressions", modern regexes give an expressive power that far exceeds the (Click link for more info and facts about regular language) regular languages.
		Regex matching with an unbounded number of back references, as supported by a number of modern tools, is (Click link for more info and facts about NP-complete) NP-complete.
	www.absoluteastronomy.com /encyclopedia/r/re/regular_expression.htm (2674 words)

	Steve's place - Perl Tutorial Lesson 18
		Grammars, of which regexes are the most basic sort, are what you use to describe, parse, and grasp the meaning of a language.
		One problem of Perl 5 regexes is that although they are not very regular, they are still not capable of matching balanced pairs: no Perl 5 regex can determine whether a nested construct like (2 + (2 + (5 / 6) + (9 - (8 * 6)))) is correctly parenthesised or not.
		This means that the Perl 6 regex engine will be powerful enough to parse Perl itself, which is a lovely bit of bootstrapping and a Good Thing: CFGs are more powerful than regexes, and they will allow you to mess with how perl parses itself from within Perl.
	www.steve.gb.com /perl/lesson18.html (2647 words)

	[logs] Re: Generic Log Message Parsing Tool (Site not responding. Last check: 2007-11-03)
		That said, I don't have the same religious objections to regexes that you seem to; with a robust [1] regex implementation (like Perl's, or the Java ORO library).
		It's possible to have more readable regexes in perl using it's m//x syntax (which I won't go into; man perlre if you are interested), but complex regexes are very definitely reader-unfriendly.
		Again, this is true of most languages; it's possible to write a regex that won't fail to match before the heat death of the universe, but it's also possible to write exponential growth functions in other languages.
	lists.shmoo.com /pipermail/loganalysis/2002-June/000091.html (886 words)

	wish - the session mechanism should be extended to support regexes wish - the session mechanism should be extended to ... (Site not responding. Last check: 2007-11-03)
		Emacs uses an regex mechanism for syncrhonization that could be an additional scheme.
		The interest of using regexes is that you can use non instrumented clients.
		The only requirement is that it has a prompt that is matched by the regex.
	alqua.com /tmresources/WishTheSessionMechanismShouldBeExtendedToSupportRegexes (167 words)

	Perl Seminar Assignment 1 (Site not responding. Last check: 2007-11-03)
		This assignment is meant to be a simple exercise in writing basic regexes.
		These will be regexes that recognize normal patterns.
		Write two or three patterns that would be recognized by each regex.
	www.cs.wisc.edu /~hasti/cs368/Perl/assign1.html (115 words)

	WebDeveloper.com - View Single Post - Need help proofing script
		I think it would be faster not to use regexes and use strings instead.
		There is overhead involved with using regexes, although I'm not sure how much with javascript, so it's faster to avoid regexes when possible.
		I followed a post once where the guys hand a massive regex they were trying to optimize, and they strung all the replace()'s in one long chain.
	www.webdeveloper.com /forum/showpost.php?p=278820&postcount=3 (169 words)

	Regular Expressions in Perl
		The regex might look daunting now, but the secret to understanding regexes is this: like any other language, a "sentence" is made up of a series of smaller pieces, and that if you understand what each piece means on its own, you can put them together and understand the whole.
		The first one uses a regex as its first argument (except in one very special case); the other two don't require a regex to be used, but more often than not, you'll see a regex used with them.
		Regexes are quite ugly to look at, and sometimes it's helpful to embed little comments for any readers of your code to see.
	library.n0i.net /programming/perl/re_gex (12285 words)

	Regexes - Mark Cohen (Site not responding. Last check: 2007-11-03)
		Gone past the standard phone number, email address and url regexes and starting to play with some cooler regexes.
		If you use regexes at all I highly recommend you download the regex editor from rad software.
		I saw a posting on sitepoint forums tonight, someone trying to create a regex that will identify math operators in a string that are not inside of brackets.
	home.swiftdsl.com.au /~markcohen/index.php?itemid=17 (168 words)

	Re: generating regexes?
		My current approach is extremly simplistic, goes from the left, character by character and selects what it think is the most specific candidate regex that matches all the examples.
		It performs less well when the examples are of varaible length, and makes no efforts to recognize stemming between the examples.
		I guess generating the initial set shouldn't be too hard...survival critera should center around how many of the examples it matches, but somehow I'd want it to create general, but fairly specific regexes.
	lists.netisland.net /archives/phlpm/phlpm-2001/msg00661.html (322 words)

	Easy Regular Expression Builder
		If you have written regular expressions before, you know that the regex syntax can be hard to keep track of.
		RegexBuddy updates its regex tree as you type, and highlights the token that the text cursor points at.
		If your browser supports JavaScript, the corresponding regex token and regex building block will be highlighted when you move the mouse pointer over the regexp or the tree.
	www.regexbuddy.com /create.html (782 words)

	Regexp::Keep - filter to allow the C<\K> escape in regexes
		escape in your regexes, which fools the regex engine into thinking it has only just started matching your regex.
		, which is an XS function call embedded into the regex.
		This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.3 or, at your option, any later version of Perl 5 you may have available.
	cpan.uwinnipeg.ca /htdocs/Regexp-Keep/Regexp/Keep.html (237 words)

	perlfaq6(1): regex - Linux man page
		modifier causes whitespace to be ignored in a regex pattern (except in a character class), and also allows you to use normal comments there, too.
		This always happens in a constant regular expression, and in fact, the pattern was compiled into the internal format at the same time your entire program was.
		Most people mean that greedy regexes match as much as they can.
	www.die.net /doc/linux/man/man1/perlfaq6.1.html (3696 words)

	dBforums - Just curous about this- are REGEXes rigorously deterministic
		Are regexes theory, that is a proposal that cannot be proven, or are
		There is more than one valid representation for any regex in perl.
		That several regex can have the same result is clear.
	dbforums.com /t766146.html (2094 words)

	Synopsis 5: Regexes and Rules - perl6:
		We now try to call them regex rather than "regular expressions" because they haven't been regular expressions for a long time, and we think the popular term "regex" is in the process of becoming a technical term with a precise meaning of: "something you do pattern matching with, kinda like a regular expression".
		On the other hand, one of the purposes of the redesign is to make portions of our patterns more amenable to analysis under traditional regular expression and parser semantics, and that involves making careful distinctions between which parts of our patterns and grammars are to be treated as declarative, and which parts as procedural.
		modifier causes this regex and all invoked subrules to remember everything, even if the rules themselves don't ask for their subrules to be remembered.
	dev.perl.org /perl6/synopsis/S05.html (11714 words)

	search.cpan.org: Regexp::Parser - base class for parsing regexes
		Clears the parser's memory and sets $regex as the regex to be parsed.
		The regex is formed by calling the qr() method of each node in the tree, which may be different from the visual() method; specifically, in the case of a sub-class that adds a handler, the qr() method is used to produce the Perl regex implementation of the new node.
		POSIX classes don't exist in a regex outside of a character class, so I'm a little wary of making them objects in their own right, even if it would create a better sense of uniformity.
	search.cpan.org /perldoc/Regexp::Parser (2020 words)

	[No title] (Site not responding. Last check: 2007-11-03)
		For now, the dissection of the regex at the end of my Summer '04 TPJ article.
		What this regex does is match 'key=value' pairs, where the value might be quoted with "..." or '...'.
		My absurd regex gets around this by matching the quotes outside the capture group if they're going to exist.
	japhy.perlmonk.org /regexes (227 words)

	Regular-Expressions.info - Regex Tutorial, Examples and Reference - Regexp Patterns
		Compose and analyze regex patterns with RegexBuddy's easy-to-grasp regex blocks and intuitive regex tree, instead of or in combination with the traditional regex syntax.
		A regular expression (regex or regexp for short) is a special text string for describing a search pattern.
		This tutorial is quite unique because it not only explains the regex syntax, but also describes in detail how the regex engine actually goes about its work.
	www.regular-expressions.info (705 words)

	O'Reilly: C# Regular Expressions
		Let's start with simple expressions using the Regex and the Match class.
		, if the regex engine matches the expression to that which is found in the text.
		Then the second capture group, marked by the second parenthesis, begins, but the definition of the first capture group is still ongoing.
	windows.oreilly.com /news/csharp_0101.html (1815 words)

	[Biojava-dev] Regexes and sequencing searching (Site not responding. Last check: 2007-11-03)
		A change in the sequence implementation does not affect my symbollist regex package as it uses various tricks to reduce slow symbol access.
		Evidently there is a tradeoff between being able to have the whole sequence in RAM and swapping and comparative sizes of our packed representation and a String to consider in any final decision.
		Pros: Can search in any alphabet including those that cannot be handled with java.util.regex because of the absence of a suitable tokenization (large numbers of symbols).
	www.biojava.org /pipermail/biojava-dev/2004-April/001370.html (335 words)

	Re: range of characters in regexp in locale aware environment (Re: Bug#281368: sed: regexes fail on et_EE.UTF-8 locale)
		You said "many users misunderstand range of characters machtes" but the regex is from autoconf code - should use of a-z be reported as bug in package or should users in weird locales expect such failures?
		Prev by Date: Re: range of characters in regexp in locale aware environment (Re: Bug#281368: sed: regexes fail on et_EE.UTF-8 locale)
		Previous by thread: range of characters in regexp in locale aware environment (Re: Bug#281368: sed: regexes fail on et_EE.UTF-8 locale)
	lists.debian.org /debian-i18n/2004/11/msg00011.html (404 words)

	ZopeLABS - Arbitrary Regular Expressions (Site not responding. Last check: 2007-11-03)
		There may well be a good reason you can't use regexes in Python Scripts,
		regexes, it doesn't make much sense to globally permit it.
		regex goodness while maintaining control with the standard zope security tools.
	zopelabs.com /cookbook/1084823616 (335 words)

	How Regexes Work
		Although this article purports to describe "How Regexes Work", it describes only one possible technique.
		They are somewhat telegraphic in style, because they are designed to accompany a lecture, and not to stand on their own.
		A sidebar explains the academic terminology that I didn't use in the article.
	perl.plover.com /Regex (201 words)

	Readable Regexes: The Regular Expressions DSL
		Which is impressive, since I use Regulator all the time to deal with regexes.
		What it more, for about the first time ever, this allow me to consider building a regular expression on the fly.
		I wrote about an idea for a higher level RegEx syntax that compiles to that regex gobbleygook last year:
	www.ayende.com /Blog/archive/2006/10/23/7159.aspx (172 words)

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