Two interesting comments from Michael Kay

["Costello, Roger L." <costello@mitre.org>]

Hi Folks,

1. On November 4, 2011 Michael Kay wrote on the SAXON mailing list the following. It gives an intriguing hint about how the SAXON XSD validator is implemented:

Saxon's validation of schema documents is in most cases driven by a 
finite state machine that is automatically generated from the content 
model in the schema for schema documents. So unless there are issues 
like the spec changing since the FSM was last generated, I'm fairly 
confident that Saxon gets this kind of thing right.

http://sourceforge.net/mailarchive/message.php?msg_id=28329712

2. Today Michael made an interesting statement regarding the XML Schema specification:

XSD is probably the most difficult spec I have read since Algol 68. The 
difference is that the more you read the Algol 68 spec, the more it 
makes sense; whereas the more you read the XSD spec, the more holes you 
find.

The wonder is that despite all its faults, a large number of people are 
getting a large amount of value from it.

http://lists.xml.org/archives/xml-dev/201112/msg00069.html

/Roger