Re: XSLT workflow: ODF <-> XPP

Thanks for a great reply Michael!
I was having similar thoughts.

Martynas

On Thu, May 28, 2009 at 10:55 AM, Michael Kay <mike@xxxxxxxxxxxx> wrote:
>> The problem is, that the two formats are not interchangeable,
>> and this breaks the whole workflow. They have a filter to
>> import ODF to XPP (the easy part). They also have another to
>> convert back from XPP to ODF, but it discards XPP processing
>> instructions that were added while styling. That means a
>> roundtrip is not possible, because the existing inline XPP
>> styling would be lost.
>
> This problem crops up all the time in different guises. It's the same as the
> code-generation problem: you generate some code from say a visual query
> builder, then you tweak the generated code, then you want to regenerate some
> slightly different code without losing your tweaks.
>
> There's no general solution to the problem but there seem to be a number of
> techniques that can half-solve the problem.
>
> (a) change the reverse transformation so that it doesn't discard the extra
> information (the "processing instructions" or "tweaks"), but hides them
> somewhere in the ODF where they will survive unscathed through the
> operations performed at the ODF level - if necessary, as user-visible text
> (though you can probably do better than that)
>
> (b) do a reconciliation: when the XPP is regenerated, compare it with the
> "tweaked" XPP from the previous version, and try to find where the tweaks
> are and reapply them to the new XPP version. This is a bit like merging of
> branches in CVS.
>
> (c) change the way you "tweak" the XPP so that the changes are logged as you
> make them and can be reapplied to a new version of the XPP.
>
> That's a very high-level description of ideas which might not translate
> directly into the reality of the situation, but if you don't want to lose
> the "tweaking" work then you're going to have to find something along one of
> these lines.
>
> Since you are converting the XPP back to ODF already, I would look for a
> solution along the lines of (a). A variant of this would be, instead of
> hiding the tweaks in the ODF, generate a separate file containing all the
> "tweaks", that can then be applied to the regenerated XPP, along the lines
> of (c).
>
> Regards,
>
> Michael Kay
> http://www.saxonica.com/
> http://twitter.com/michaelhkay