In this section, we address adding per-document data, in contrast to the per-element data we have been discussing until now. In a nutshell, we suggest storing document data on an element as well, simply using a singleton element, i.e. one that appears only once per document.
Problem: We need a strategy to persistently store per-document or per-model data.
Solution: Bind (hidden or visible) shared parameters to the singleton element of 'Project Information' category.
We implement two commands to test this concept, to initialise and increment.
Topics in this subsection: