RE: [xliff] Change tracking questions

[Yves Savourel <ysavourel@enlaso.com>]

Hi all,

I've spend most of the week-end and a big part of today trying to implement CTR 2.1 and I'm not making much progress. Simple
examples may work fine, but with real life content things are not working well. 

-- Out of context issues

As we store content in unitItem and contentItem, there is the issue of context that crops up: Some information like xml:space or
translate go across segment, or even across units, and may not have a physical representation in the XLIFF snippet we store.

For example taking a segment content out of the context of its surrounding other segments may hide the fact that it is not
translatable because there are some <mrk id='1' translate='no'> in the previous segment.
That information cannot be stored in <contentItem>. It may be OK, but that may also have side effect when restoring the data in a
different context.

Another illustration of context issue: <mrk type='comment' ref="#n1"> is a comment referring to a note. If we store this in, for
example, an <itemContent> because the translation has changed, there is no guaranty that the note n1 will stay there, or even point
that n1 corresponds to the same note after some other changes. So we can end up with invalid references.

Overall, it seems the content of a <revision> is bound to break the normal content constraint at some points because a) It is stored
in a different context and b) It is not stored with all its 'dependencies'.

-- Validation troubles:

We say we do not want orphan <mrk>, but there are other validation issues with the stored content.

For example the id value of a segment may exists twice: in the true content and in one (or more CTR entries). If they do have the
same values, they break the constraint of http://docs.oasis-open.org/xliff/xliff-core/v2.0/xliff-core-v2.0.html#id where the
specification says that when id is used with segment "...the value MUST be unique among all of the above (segment, etc.) within the
enclosing <unit> element."

I'm running into a lot of problems when trying to read back contentItem and unitItem.

Cheers,
-yves