[XML-DEV Mailing List Archive Home] [By Thread] [By Date] [Recent Entries] [Reply To This Message]

Re: UPA and schema handling

• To: Bob Foster <bob@o...>
• Subject: Re: UPA and schema handling
• From: Paul Sumner Downey <paul.downey@w...>
• Date: Mon, 18 Oct 2004 09:09:44 +0100
• Cc: Ian Graham <ian.graham@u...>, xml-dev@l...
• In-reply-to: <4172BD45.7040409@o...>
• References: <41729D89.6020906@u...> <4172BD45.7040409@o...>
• User-agent: Mozilla Thunderbird 0.8 (Windows/20040913)

Bob Foster wrote:
> Unique particle attribution is normative and not optional, but not all 
> processors check it correctly and some processors check it optionally. 
> Of course that leads to interoperability errors, and not just around 
> UPA, but that's the state of the art.

Whilst UPA assists a particular style of implementation, it kills a lot 
of the expressiveness of W3C schema. It certainly prevents being able to 
evolve a given schema.

It's also obvious that a processor using schema to build a code model is 
  able to ignore UPA and still get its work done.

So I wonder if there isn't a case for a standard schema 1.0 extension: a 
flag to indicate 'this schema is valid except it violates UPA 
restrictions'. It wouldn't be backwards compatible with a strictly 
compliant 1.0 schema validator, but could be useful in a specific 
processing domain such as Web services.

Paul
--
http://blog.whatfettle.com

• Follow-Ups:
  • RE: UPA and schema handling
    • From: "Michael Kay" <michael.h.kay@n...>

• References:
  • UPA and schema handling
    • From: Ian Graham <ian.graham@u...>
  • Re: UPA and schema handling
    • From: Bob Foster <bob@o...>

• Prev by Date: RE: Why *is* XQuery taking so long?
• Next by Date: xml tool
• Previous by thread: Re: UPA and schema handling
• Next by thread: RE: UPA and schema handling
• Index(es):
  • Date
  • Thread