simple installation of old port versions (was: Lion Recovery Partition)

[Joshua Root]

On 2011-10-18 02:11 , Arno Hautala wrote:
> On Mon, Oct 17, 2011 at 10:53, Jeremy Lavergne
> <jeremy at lavergne.gotdns.org> wrote:
>>> Tie in for what reason?
>>>
>>> What's your higher goal with the recovery partition / TimeMachine.
>>
>> We've had a recent thread (I think on -users) about making the
>> installation of previous portfile versions easier.

A fairly obvious enhancement that is enabled by having binaries on a
server is, when the user types 'port install foo @bar', attempting to
download version bar. (The error reporting needed for this feature alone
would actually fix #24520.)

All the usual gotchas of installing an older binary would apply of
course. Adding version ranges to dependencies would be the fix for most
of them, and being able to fetch particular versions would allow
dependencies on old versions to be handled automatically.

This of course opens its own can of worms regarding detecting and
resolving dependency conflicts. Getting that working well would put us
in the position of having that new dependency engine that's been talked
about for so many years.

- Josh