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RE: [XaraXtreme-dev] Text margin support

In message <5056CBC646CB4047BB26120F4377DB71DC79EC@xxxxxxxxxxxxxxxxxxx 
          "Phil Martin" <Phil@xxxxxxxx> wrote:

> FYI:
> XAR files don't have a "file format version" because that's not a useful
> concept when different parts of the format can change at any time and
> the rest of the file is loadable by older versions. (We learnt that from
> ArtWorks.)
> The versioning is done at record level and is entirely based on the
> record TAG numbers themselves. Any format changes require a new record
> TAG so that older loaders can't be confused by changes in records they
> think they understand.
> If you add a new compound tag then you should mark it as "Atomic" so
> that older loaders will skip that entire subtree.
> If you add a new tag that's critical to the correct loading/rendering of
> the file you can mark it as "Essential" so that older loaders will abort
> if they encounter it.

Thanks, that sounds like a very good approach.