ubl and extension

[Patrick Garvey <pgarvey@SIMS.Berkeley.EDU>]

Hi. I've heard talks and read papers about how UBL documents are intended
to be extended in verticals with information specific to that vertical.
This is the notion of context, I believe.

Perhaps it is still undecided, but I am wondering at what level of the
document is it intended that the extension take place?

As a simple example, if I wish to extend a UBL Order so that the
information specific to my industry is expressed, should I extend the
OrderType? Or do I extend something further down in the document, like the
LineItemType? Or should I just extend whatever I need to extend to get the
job done? Are the documents being designed with the intent that certain
types/elements are natural extension points, and other types/elements
should probably remain consistent across verticals?

thanks,

Patrick