On 1/6/15 7:16 AM, Usman Bhatti wrote:
Dale,
I couldn't make it work with the upgraded Metacello and the script you
provided.
Steps I did:
1. Download moose image:
https://ci.inria.fr/moose/job/moose-5.0/
2. Update my Metacello to the 'full' version:
Metacello new
baseline: 'Metacello';
repository: 'github://dalehenrich/metacello-work:master/repository';
get.
Metacello new
baseline: 'Metacello';
repository: 'github://dalehenrich/metacello-work:master/repository';
onConflict: [:ex | ex allow];
load
3. File in the ConfigurationOfDummyParser (see the first message in
the thread).
4. Run this script to downgrade to PetitParser version 1.51
Metacello new
configuration: 'DummyParser';
version: '1.0';
repository: '???';
onDowngradeUseIncoming: #('PetitParser');
load.
The desired version is still not loaded, am I missing something here?
Good question, I don't have a lot of time today to spend time trying to
reproduce your problem, but if you send me a copy of the Transcript
produced while doing the load I might be able to spot the problem ...
regards,
A question: I always use Metacello with ConfigOf and have never used
the scripting API myself or saw it being used elsewhere.
Can you provide a link that describes the use cases for both: ConfigOf
vs. Scripting API?
I've noticed the same thing:)
My "elevator pitch" for the script api goes like this:
1. The scripting api maintains a registry of the actual project
versions loaded into the image,
making #currentVersion obsolete. #currentVersion is bad because
it does a calculation of
the current version that can be very slow and sometimes
completely incorrect.
2. The old api has rules that it follows when loading projects
(i.e., newer projects always win) and
there is no mechanism for altering those rules. The scripting
api provides mechanisms for
for bending those rules to fit your needs ... like allowing a
downgrade of a project.
Part of the reason that people haven't changed has to do with how
incredibly difficult it is to change the existing inertia. Another part
of it is that I continue to support the old way of doing things, so
there is no explicit motivation to change.
If you look back 2-3 years in the archives of the Metacello mailing
list[1] you should be able to find a number of posts where I make a more
detailed cases for the scripting api:)
At the end of the day, it isn't important to me to "get people to use
the scripting api," as I said, I continue to support using the old api.
I figure that when enough people start asking questions about how to
"bend the Metacello rules" that folks will begin to use the "new"
scripting api:)
Dale
[1] https://groups.google.com/forum/#!forum/metacello
