On the migration front, when someone ports Digest.pm to Perl6, I get a "free" upgrade, assuming the module author was kind enough to up the version number.

You are making a pretty huge assumption here that whoever has a namespace in p5 CPAN has first dibs at the P6 namespace of the same name, and that they will do a straight port over.

Someone else could reimplement the module for Perl 6, or perhaps the author wants to (desperately needed in some cases)completely overhaul the module and API based on lessons learnt the first time.

The problem with automatic fallback is simple that you are no longer getting two different versions of the same module, you are getting two completely different libraries, with no guarentee that the API is consistent.

Automatic fallback lets changes in environment leak into the process and cause unexpected changes in program functionality, and this is BAD.

The only time at which having to do nothing to load a current CPAN module will be during the transition period, before a suffucient body of Perl 6 modules have built up.

In the longer run, much better to have to do something special to get the old and redundant versions of modules.

Adam K

Reply via email to