fdo 50950 make (ISO)WEEKNUM comply with ODFF1.2, advise asked

[Winfried Donkers]

 Hi Eike,

> All your comments have been processed in the code (I learned some new
> things too, thank you !).
> It now works fine for all possible argument values, including leaving out the
> optional value for WEEKNUM and illegal arguments.
> 
> Now I will start on seeing how old-style documents are interpreted and how I
> can handle that as 'smooth' as possible (unnoticeable for user, I mean).
> 
> (It may be after my holidays before you hear from again)

I have searched a bit and found some functions in sc/source/core/tool/compiler.cxx that might be extended to convert old-style ISOWEEKNUM() use when reading old (pre ODFF1.2) documents. Unfortunately alle these functions seem te be called too when entering a function in an existing (open) sheet or recalculating.
It will be probably most efficient to convert only when reading a saved document.
Can you give any hint(s) as where I might put the conversion code for old-style ISOWEEKNUM() to ODFF1.2?

Winfried