Or... really i'm not sure what is the Right Solution, but at least I read of a couple of prototypes that achieved to load multiple versions of classes and methods, so it is technically feasible. The magic of Smalltalk!


On Fri, Mar 1, 2013 at 7:54 PM, Martin Dias <tinchodias@gmail.com> wrote:
I'm sorry but AFAIK you won't be able to materialize in 1.8.x the files you serialized with 1.8. Maybe Max has some trick to do it?

And you are true: tanker needs fuel so it won't work :)

Some time ago we thought in a nasty way of have two versions of fuel at the same time: take a fuel version, then rename all extension methods adding a prefix. But it's ugly and it should be done with care.�

This year I�realised�that it is possible to hack the image to enable several versions of the same package at the same time. I should ask Marcus again about this, I think it should be a good solution. Others in this mailing-list can correct me, but IMO to do it well, we first need a good modules system... but before maybe we can do some hacky solution to easy migration of files. It could be fun.

Martin




On Fri, Mar 1, 2013 at 5:53 PM, Yanni Chiu <yanni@rogers.com> wrote:


On 01/03/13 10:10 AM, Max Leske wrote:

On 01.03.2013, at 15:36, Martin Dias <tinchodias-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:


On Mon, Feb 25, 2013 at 10:55 PM, Yanni Chiu <yanni-bJEeYj9oJeDQT0dZR+AlfA@public.gmane.org> wrote:

Would it be easy to unload Fuel 1.9 from Pharo-2.0, and load Fuel 1.8
instead?

I tried to load Fuel 1.8 in Pharo 2.0 but it seems that there is an
incompatibility with Date and DateAndTime�

Should work from 1.8.1 on upwards though...

The description for 1.8.1 says:

- same as 1.8
- fix: serialization / materialization of Date objects.

The description for 1.8.2 says:

- Date / DateAndTime are now serialized consistently across different images (Squeak and Pharo)

So, the question is: will something serialized by 1.8, load into 1.8.1, 1.8.2? I guess I'll find out shortly.

My other option is to do the migration to 1.9 in Pharo-1.4, before moving to Pharo-2.0. BTW, the slowest part of a migration is upgrading the Fuel version for each set of Fuel files being migrated. Do you think it would work to have a Fuel Tanker file for Fuel version 1.9, that can be quickly loaded? Hold on - that would mean you'd need some version of Fuel loaded.