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

Re: Validating IDREFS...

  • From: David Megginson <david@m...>
  • To: xml-dev@i...
  • Date: Sun, 30 Aug 1998 07:17:44 -0400

Re: Validating IDREFS...
Tyler Baker writes:

 > > You need to maintain a hash table of IDs in order to enforce the ID VC
 > > (uniqueness of IDs).  To check matching of IDs you just add a boolean
 > > that says whether the ID has been defined yet.  At the end of the
 > > document, iterate over the hash table and give an error for each
 > > undefined ID.
 > 
 > This I know is one idea to get around this problem and this is
 > basically my current implementation as well, but shouldn't a
 > validating XML parser flag an error if an IDREF does not have a
 > corresponding ID when the error occurs.  In other words, I would
 > think that deferring errors before the content is passed to the
 > document would be illegal.

Here are three points to note:

1. It is more important to pass information to the application about
   _where_ the error occurs, and you can keep that information in the
   hash table.

2. In a tree-based API, the error will be spotted before the tree is
   completed, so the application will know about the error right at the
   start before it can work with the tree.

3. In a stream-based API, the error will be obvious when you have
   parsed the end tag of the document element -- you can report the
   error before you report the element end.


All the best,


David

-- 
David Megginson                 david@m...
           http://www.megginson.com/

xml-dev: A list for W3C XML Developers. To post, mailto:xml-dev@i...
Archived as: http://www.lists.ic.ac.uk/hypermail/xml-dev/
To (un)subscribe, mailto:majordomo@i... the following message;
(un)subscribe xml-dev
To subscribe to the digests, mailto:majordomo@i... the following message;
subscribe xml-dev-digest
List coordinator, Henry Rzepa (mailto:rzepa@i...)


PURCHASE STYLUS STUDIO ONLINE TODAY!

Purchasing Stylus Studio from our online shop is Easy, Secure and Value Priced!

Buy Stylus Studio Now

Download The World's Best XML IDE!

Accelerate XML development with our award-winning XML IDE - Download a free trial today!

Don't miss another message! Subscribe to this list today.
Email
First Name
Last Name
Company
Subscribe in XML format
RSS 2.0
Atom 0.3
 

Stylus Studio has published XML-DEV in RSS and ATOM formats, enabling users to easily subcribe to the list from their preferred news reader application.


Stylus Studio Sponsored Links are added links designed to provide related and additional information to the visitors of this website. they were not included by the author in the initial post. To view the content without the Sponsor Links please click here.

Site Map | Privacy Policy | Terms of Use | Trademarks
Free Stylus Studio XML Training:
W3C Member
Stylus Studio® and DataDirect XQuery ™are products from DataDirect Technologies, is a registered trademark of Progress Software Corporation, in the U.S. and other countries. © 2004-2013 All Rights Reserved.