Editing Perl (section)

=== 1990s ===
{{Main|Perl 5 version history}}

Originally, the only documentation for Perl was a single lengthy [[man page]]. In 1991, ''Programming Perl'', known to many Perl programmers as the "Camel Book" because of its cover, was published and became the ''de facto'' reference for the language.<ref>{{Cite web |title=Programming Perl, 3rd Edition [Book] |url=https://www.oreilly.com/library/view/programming-perl-3rd/0596000278/ |access-date=2023-04-11 |website=www.oreilly.com |language=en}}</ref> At the same time, the Perl version number was bumped to 4, not to mark a major change in the language but to identify the version that was well documented by the book.<ref>{{Cite web |title=perlhist - the Perl history records - Perldoc Browser |url=https://perldoc.perl.org/perlhist |access-date=2023-07-28 |website=perldoc.perl.org}}</ref> Perl 4 was released in March 1991.<ref name="Kalita"/>

Perl 4 went through a series of [[maintenance release]]s, culminating in Perl 4.036 in 1993, whereupon Wall abandoned Perl 4 to begin work on Perl 5. Initial design of Perl 5 continued into 1994. The ''perl5-porters'' [[mailing list]] was established in May 1994 to coordinate work on porting Perl 5 to different platforms. It remains the primary forum for development, maintenance, and porting of Perl 5.<ref>{{Cite web |url=http://www.nntp.perl.org/group/perl.perl5.porters/ |title=perl.perl5.porters archive |access-date=2011-01-13 |publisher=perl.org |archive-date=May 1, 2011 |archive-url=https://web.archive.org/web/20110501081803/http://www.nntp.perl.org/group/perl.perl5.porters/ |url-status=live}}</ref>

Perl 5.000 was released on October 17, 1994.<ref name="perlhist">{{Cite web |url=http://perldoc.perl.org/perlhist.html |title=perlhist: the Perl history records |access-date=2011-01-21 |work=Perl 5 version 12.2 documentation |publisher=perldoc.perl.org |archive-date=January 13, 2011 |archive-url=https://web.archive.org/web/20110113030100/http://perldoc.perl.org/perlhist.html |url-status=live}}</ref> It was a nearly complete rewrite of the [[interpreter (computing)|interpreter]], and it added many new features to the language, including [[Object (computer science)|objects]], [[Reference (computer science)|references]], [[Local variable|lexical (my) variables]], and [[Modular programming|modules]]. Importantly, modules provided a mechanism for extending the language without modifying the interpreter. This allowed the core interpreter to stabilize, even as it enabled ordinary Perl programmers to add new language features. Perl 5 has been in active development since then.

Perl 5.001 was released on March 13, 1995. Perl 5.002 was released on February 29, 1996 with the new prototypes feature. This allowed module authors to make [[subroutine]]s that behaved like Perl [[Shell builtin|builtins]]. Perl 5.003 was released June 25, 1996, as a security release.<ref>{{Cite web |title=Perl: Definition, History, & Facts |url=https://www.britannica.com/technology/Perl |access-date=2022-06-15 |website=Britannica.com |language=en}}</ref>

One of the most important events in Perl 5 history took place outside of the language proper and was a consequence of its module support. On October 26, 1995, the [[CPAN|Comprehensive Perl Archive Network]] (CPAN) was established as a [[Software repository|repository]] for the Perl language and [[Perl module]]s; {{as of|December 2022|lc=y}}, it carries over 211,850 modules in 43,865 distributions, written by more than 14,324 authors, and is mirrored worldwide at more than 245 locations.<ref>{{Cite web |url=https://www.cpan.org/ |title=CPAN |access-date=2022-12-19 |publisher=[[CPAN]] |archive-date=October 3, 2019 |archive-url=https://web.archive.org/web/20191003040107/https://www.cpan.org/ |url-status=live}}</ref>

Perl 5.004 was released on May 15, 1997, and included, among other things, the UNIVERSAL package, giving Perl a base object from which all [[Class (computer programming)|classes]] were automatically derived and the ability to require versions of modules. Another significant development was the inclusion of the [[CGI.pm]] module,<ref name="5004delta">{{Cite web |url=http://perldoc.perl.org/perl5004delta.html |title=perl5004delta – what's new for perl5.004 |access-date=2011-01-08 |work=Perl 5 version 12.2 documentation |publisher=perldoc.perl.org |archive-date=February 27, 2011 |archive-url=https://web.archive.org/web/20110227200616/http://perldoc.perl.org/perl5004delta.html |url-status=live}}</ref> which contributed to Perl's popularity as a [[Common Gateway Interface|CGI scripting language]].<ref name="patwardhan02">{{Cite book |last1=Patwardhan |first1=Nathan |last2=Siever |first2=Ellen |last3=Spainhour |first3=Stephen |title=Perl in a Nutshell, Second Edition |publisher=[[O'Reilly Media]] |year=2002 |isbn=978-0-596-00241-1 |url=https://archive.org/details/perlinnutshell00patw}}</ref>

Perl 5.004 added support for [[Microsoft Windows]], [[Plan 9 from Bell Labs|Plan 9]], [[QNX]], and [[AmigaOS]].<ref name="5004delta"/>

Perl 5.005 was released on July 22, 1998. This release included several enhancements to the [[Regular expression|regex]] engine, new hooks into the backend through the <code>B::*</code> modules, the <code>qr//</code> regex quote operator, a large selection of other new core modules, and added support for several more operating systems, including [[BeOS]].<ref name="5005delta">{{Cite web |url=http://perldoc.perl.org/perl5005delta.html |title=perl5005delta - what's new for perl5.005 |access-date=2011-01-21 |work=Perl 5 version 12.2 documentation |publisher=perldoc.perl.org |archive-date=February 3, 2011 |archive-url=https://web.archive.org/web/20110203100249/http://perldoc.perl.org/perl5005delta.html |url-status=live}}</ref>