LVOOP Class Versioning, saving to file

Question

I'm storing LabVIEW objects to file.  What is the best way to re-load these objects even if the class version has changed?  Generally I've found that this causes few problems and the classes are able to adapt, except when I've made major changes to the class definition typedef.  Is there a way to write an adapter VI that checks the class version of the stored class and up-converts appropriately?
Also, are there any good resources for general "best practices" related to LVOOP, for versioning, working as a team, etc.?

Answer 1

Unfortunately when loading previous classes there doesn't seem to be a way to have tight control over how old versions are converted up. The conversion (hopefully I remember the details right) depends on how they where changed within the editor, if you rename a field then the data for the old name when be placed into the new name, if you remove the field and replace it then the data for the old filed will be deleted and the new one will take the default value).
You'll want to avoid typedefs (classes should be fine) within class data, since typedefs don't maintain their mutation history.
http://lavag.org/topic/14548-class-mutation-history/
Enums can also be a problem
http://forums.ni.com/t5/LabVIEW-Idea-Exchange/Maintain-Mutation-History-as-part-of-Enum-Type-Definit...
Hopefully some version of LabVIEW will allow more control over version mutation, but currently you would need to be very careful with the the class data. SVN (or some other file versioning system), could be helpful for backtracking if you mess up modifying the class data (just don't go before the last in use version, since that may break the mutation system).
To have to full control you would need to flatten your data manually. If you want to go that route converting things to variants then using flatten to string is a simple way of storing type data with the real data.