- From: Tim Bray <tbray@textuality.com>
- Date: Thu, 13 Jun 2002 11:14:09 -0700
- To: "Simon St.Laurent" <simonstl@simonstl.com>
- Cc: www-tag@w3.org
Simon St.Laurent wrote: > XQuery has taken a stab at reducing the PSVI to something manageable, > yes. (See [s1].) This is exactly the problem. I quote from http://www.w3.org/TR/query-datamodel/#psv "The data model is defined in terms of the [XML Information Set] after XML Schema validity assessment. XML Schema validity assessment is the process of assessing an XML element information item with respect to an XML Schema and augmenting it and some or all of its descendants with properties that provide information about validity and type assignment. The result of schema validity assessment is an augmented Infoset, known as the Post Schema-Validation Infoset, or PSVI. " It's just fine to want to use types and so on in XQuery (or any other work). It's simply wrong to assert that types can exist only "after XML Schema validity assessment." There is no way in the world to discover that some attribute value should be interpreted as a floating point number for purposes of range comparison, other than ascertaining whether the containing instance is valid? An analogy: the PSVI is kind of like saying that the only way to ascertain a person's weight is to go through a complete top-to-bottom physical exam." -Tim
Received on Thursday, 13 June 2002 14:12:03 UTC