Re: Trimming the CPAN - "Automatic Purging"

> It hasn't been done because its outside of the scope of design for rsync.
> It's meant to sync arbitrary filesets in which many, if not all, changes are
> made out of band.  It's decidely non-trivial to implement in that mode
> unless you're willing to accept a certain window in which your database may
> be out of date.
>
> But, in a situation like PAUSE, where the avenues in which files can be
> introduced into the file sets is controlled, it does become trivial.  It's
> the gatekeeper, it knows who's been in or out.

so the requirements for the Solution To The Problem Which Solves A
More General Problem Than The Immediate Problem And Will Therefore
Make Whoever Sets It Up A Hero include a replacement for the current
mirroring technology stack that is tailored to mirroring distributions
possibly including on-demand caching and expiration and that is
trivial to install -- something like

  perl -MCPAN -e 'install STTPWSAMGPTTIPAWTMWSIUAH::Mirrorsuite'
  nohup nice nice perl -MSTTPWSAMGPTTIPAWTMWSIUAH::Mirrorsuite -e
'mirror cpan.org .' &