Re: [xml-dev] "Introducing MicroXML, Part 1: Explore the basic principle

[Michael Kay <mike@saxonica.com>]

 >So I don't think elements provide what PIs do: if elements were 
satisfactory, people would use elements.

We had an interesting debate during XSD 1.1 development on whether PIs 
(and comments) should be visible to assertions. On the one hand, people 
felt there should be a way for the schema to control whether PIs were 
allowed or not. But other people felt that the whole point of PIs is 
that enable document authors and recipients to get around restrictions 
imposed by unimaginative schema designers.

The final outcome was: By default, comments and processing instructions 
are excluded from the partial ˇpost-schema-validation infosetˇ [visible 
to an assertion], but ˇat user optionˇ processors may retain comments 
and processing instructions instead of excluding them. (Saxon supplies 
such an option.)

Michael Kay
Saxonica