Make API versioning compiler evaluable

[Michael Stahl]

On 11.04.19 09:32, Jan-Marek Glogowski wrote:
> * Has UDK an independent versioning, or is it also the Office version?

it used to have independent versioning in OOo days, although looking at 
@since tags in include/rtl that is evidently replaced by LO versioning now.

> More comments?

i'm not sure if it is worth the effort - we generally discourage C++ 
extensions anyway since Java or Python extensions have a lot less 
pitfalls; Java doesn't have a preprocessor, and so the way to build 
against an old API is to just put a corresonding old jar on the 
classpath; Python doesn't even have static typing so it's not applicable.

also, if you look at the URE headers, almost any new addition in the 
last years is behind #ifdef LIBO_INTERNAL_ONLY anyway.