painting types

["Simon St.Laurent" <simonstl@simonstl.com>]

I've been pondering various infosets lately, wondering if it's possible for 
us to 'all just get along'.  The transition from clean labeled structures 
to clean labeled typed structures seems to be producing a lot of conflict 
along the way, and I'm starting to wondering if maybe it's time for a 
lateral move.  (Yes, I know that's Rick Jelliffe's specialty, but I'll give 
it a try.)

It seems to me that a lot of the issues surrounding the PSVI are tied to 
the mixing of type description and constraints assignment.  Schema 
validation is validation against a set of rules, and also adds information 
about typing to the document.

It seems like it would be useful to have a mean of identifying types in 
documents which doesn't involve defining those types and which doesn't rely 
on validation processing per se to get work done.  Henry's complained that 
W3C XML Schema's competitors don't address this issue, so perhaps it would 
be a worthwhile supplement.

CSS already uses a 'painting' approach with formatting, and RDF seems 
capable of doing similar things as metadata.

I can't say that I would mind seeing something like:

invoice {type:invoice;}
invoice invoiceNum {type:integer;}
invoice date {type:date;}
invoice item {type:item;}

to use ad hoc CSS syntax as I sit here at a payphone on a 7.2bps connection.

Seems like there'd be a lot of room to run with this, and it could be 
genuinely useful in a wide variety of cases.

Simon St.Laurent
Associate Editor
O'Reilly and Associates