CPAN

Comprehensive Perl Archive Network, http://cpan.perl.org/

On twiki.org you can write InterWiki links for CPAN modules, such as CPAN:CGI, CPAN:Digest::SHA1, etc.

• HowToInstallCpanModules - install CPAN modules, with or without admin privileges
• CpanPerlModulesRequirement - policy on TWiki use of CPAN modules

Contributors: MartinCleaver, RichardDonkin, PeterThoeny - 13 Oct 2006

Discussions

Basically, if you have written a perl module you can make it available to others by uploading it to the CPAN website. Hence, if you are looking to write a piece of functionality using Perl you should check on cpan.Perl.org before starting and extend what's there in preference to reinventing the wheel.

The policy about TWiki's use of CPAN modules is, to date, unclear. Check the discussions on CpanPerlModulesRequirement.

-- - 20 Aug 2002

I think the policy is quite clear (minimal use of modules, see ReadmeFirst), it's just a question of what to do when a module would be helpful.

-- RichardDonkin - 21 Aug 2002

I think it would be useful to add that CPAN modules that consist of only Perl code are okay (and, I think, encouraged) whereas those that have bridges to compiled code or external libraries are not just due to the extra level of complexity.

I think we need to encourage use of CPAN modules bundled in the TWiki standard bundle. We also need to get rid of some code we copied from standard CPAN modules, such as the Date code in TWikiDotPm.

-- MartinCleaver - 29 Aug 2002

Even modules that are Perl only are quite painful to get installed in some environments - see JohnTalintyre's comments in CpanPerlModulesRequirement for example. Particularly where you don't have Internet access, or when there is a separate system administrator who installs Perl modules. Unfortunately the CPAN.pm module makes it quite hard to install modules to a separate tree under the TWiki administrator's home directory, and few people know how to do this, so it is often necessary to involve a system administrator.

So I would say that CPAN modules should be used where they provide a big gain in functionality or simplifying TWiki code. I don't think that simplifying date code qualifies, as this is quite simple - the pain in installation doesn't justify the code saving IMO.

-- RichardDonkin - 29 Aug 2002

I have put in an InterWiki link so we can now link to CPAN:CGI, CPAN:Digest::SHA1, etc.

-- RichardDonkin - 07 May 2003