Since, we have not found any simple way to handle the rules of
different structures in a general way, this would typically be
something solved by creating a web service using the primary web
services generated. This higher order service would then be used to
implement the rules involved.
Another possibility for a specific, known scenario is to model a
"container" or "buffer" structure which would then be used by web
services implementing composed methods using custom methods.
Best regards,
Joar