Again analogy. Remember that 02packages.details.txt.gz as dist'd by cpan contains the following: module, version, dist. So each module has a version or undef. So there really is a "current" concept of mapping a hash->module->dist as "current".

Sure, but it's CPAN.pm that reads 02packages.details.txt.gz, not perl. Maybe I didn't fully understood what you want to do, but if you want be able to write things like 

use My::Module 'sha1:DEADBEEF... or above';

[download]

and have perl verify that checksum, then perl needs to have access to that database, not only cpan. And it would need to store all hashes of all previous versions of all installed modules - which seems a bit like overkill.

Actually I'm working on a module in which I hope to incorporate some of these ideas

Ah, maybe I jumped to conclusions while reading the "perl core support" from the subject line.

In reply to Re^3: <pkg>::VERSION, git, hashes, shipit, Class::MOP, Moose, perl core support - what NOW makes sense. by moritz
in thread <pkg>::VERSION, git, hashes, shipit, Class::MOP, Moose, perl core support - what NOW makes sense. by otto

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