CHAPTER 1

CPAN

T

HE

 C

OMPREHENSIVE

 P

ERL

 A

RCHIVE

 N

ETWORK

(CPAN) is an Internet resource con 

taining a wide variety of Perl materials modules, scripts, documentation, and 

Perl itself that are open source and free for all to download and use. CPAN has 

more Perl modules available than any other resource, including modules for 

almost every conceivable task from database access to GUI development and 

everything in between. The primary gateway to CPAN is http://www.cpan.org.

No other programming community has a resource like CPAN. CPAN enables 

the Perl community to pool its strength and develop powerful solutions to difficult 

problems. Once a module is available on CPAN, everyone can use it and improve 

it. Only the most unusual Perl project needs to start from scratch.

CPAN is more than just a repository it's a community. The modules on CPAN 

are released under open source licenses, and many are under active development. 

Modules on CPAN often have mailing lists dedicated to their development with 

hundreds of subscribers.

As the name implies, CPAN is a network. CPAN servers around the world 

provide access to the collection. See the  Network Topology  section later in this 

chapter for details.

Why Contribute to CPAN?

CPAN thrives on the time and energy of volunteer programmers. You may be sur 

prised that so many talented programmers are willing to work for free. Some CPAN 

programmers aren't actually donating their time they're being paid to work on 

CPAN modules! This is certainly the minority, so let's look at some other reasons to 

join the CPAN community.

The Programmer's Incentive

For the lone programmer, contributing to CPAN is an excellent way to show the 

world your programming savvy. A programmer's resume is only an introduction; a 

smart employer wants proof. This can be hard to provide if all your work has been 

on closed source projects. Open source software is easy to evaluate if you're 

good, employers will know it immediately. There's nothing quite like walking into 

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