usage vs type, progress on includes/excludes

I had said that I would not be introducing page types (i.e. application types) into CompStrm-1. Well, I've been thinking that usage is orthogonal to types and there are things I can do with usage.

The idea here is that a DataSet can be used for more than just pages, specificly for comments (non-performing journal entries) and ledgers. (More on these two new uses in subsequent blogs.)

The idea here is that type defines wholeness (descriptor), while usage defines partness (classifier). So different uses of a given type may give rise to different rules about how an object relates to other objects that are not a part of it, while type controls how the various parts of an object work together. Specificly, for operations which effect how an object works with other objects, usage will dictate applicability (in the simplest case) and or might even define such operations.

Now type is something that does not change in the lifetime of an object. But usage can change. A ledger can become a page (promotion), or a page may become a ledger in another page (demotion).

Meanwhile progress has been good on includes and excludes. The commands work (inc, exc, rmc) and the page display now lists includes and excludes. Next I want to update the cit command to list include/exclude citations. But I still need to update topics and name resolution to use includes and excludes, so the fun part still needs to be done.

But before moving the CompStrm1 Wiki from development to maintenance, I am seriously considering adding comments and ledgers.