A Guide to Versions in Perl
Version numbers in Perl are very important; they allow orderly updating and maintenance of modules and distributions across the CPAN, and allow CPAN modules and consumers to require the versions of modules with the bugfixes or features they need. However, in this context, they are also a very unique beast with a complex and bumpy history that leads to some surprises for those who are not familiar with the nuances. These are the things CPAN authors should know about versions in Perl, and are nice for consumers to know as well.
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