[Modules] Object migration/transformation (was Re: [GOODIE] Connectors pre-release version (for 3.2))

Göran Hultgren gohu at rocketmail.com
Mon Mar 25 19:25:21 UTC 2002


Hi alL!

--- Ned Konz <ned at bike-nomad.com> wrote:
[SNIP]
> How did you get the object conversion preamble/postscript code to work?

These issues are currently being discussed in another thread - check Henrik's recent postings for
answers.

Basically he said (correct me if I am wrong etc.etc) that:

- A regular Module is and should be "dead code". They are not intended to have
preambles/postscripts. But they do have class initialization so that can possibly be used for some
things.

- DeltaModules on the other hand are the "bad boys" of the Module system which take care of the
dirty work and they will/should/could have the equivalence of pre/post-stuff. Currently they do
not though, DeltaModules are still in a flux and are not fully implemented.

[SNIP]
> I'm not too clear on how to do this in the new Modules code...

I don't think anyone is clear on how these things should work. :-) Object migration problems are
generally tricky. Perhaps we should see if we couldn't handle many of these migration problems in
a more... declarative way. Personally I haven't used pre/post-stuff that much so I don't really
know how they mostly are used but IF they are mainly used for rather trivial migration problems
then perhaps we should add some form of "rigour" to it and instead add some support to
DeltaModules to specify those migrations/transformations in a declarative way?

It would sure make the modules system "safer" than having arbitrary code running... And it could
tell you what it's doing, perhaps be able to revert/undo, warn and even abort depending on
personal Preferences etc.

Just my 2 cents, regards Göran

=====
Göran Hultgren, goran.hultgren at bluefish.se
GSM: +46 70 3933950, http://www.bluefish.se
"Department of Redundancy department." -- ThinkGeek

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