W3C home > Mailing lists > Public > www-ql@w3.org > July to September 2003

Re: creation order vs. document order

From: Jan Hidders <jan.hidders@ua.ac.be>
Date: Wed, 24 Sep 2003 17:08:12 +0200
Message-ID: <3F71B35C.5030401@ua.ac.be>
To: www-ql@w3.org

Hello Mary,

Mary Fernandez wrote:
> 
> In the [XQuery 1.0 and XPath 2.0 Data Model], Section 4.3,
> there is a set of constraints on element nodes. #3 is
> the one that you are looking for:
> 
> "Element nodes must satisfy the following constraints.
> 
>      [....]
>         
>      3. The sequence of nodes in the children property is ordered and
>         must be in document order. ... etc..."

Indeed, that was exactly what I had overlooked and only realized afterwards.

> In the [XQuery 1.0 and XPath 2.0 Formal Semantics], Section 2.2 gives
> a formal notation for the XQuery Data Model, but it _does not_ repeat
> the constraints specified in the data model document.  The editors
> are working right now to make the relationship between documents
> more clear and to identify normative vs. informative text.  I will
> make a note to refer to the data model constraints explicitly in 
> Section 2.2.

That certainly would have helped. In all modesty I think that if I'm 
having trouble understanding the formal semantics, then some other 
people are probably also having a hard time getting their head around 
it. That's actually one of the reasons why we are trying at the moment 
to come up with a formal semantics for a small but relevant subset of 
XQuery that can be used to do (database or other) theory.

Having said that, I still think that the problem with the content 
construction for new elements *is* a real problem (although easy to fix) 
but I refer for that to my reaction to Peter's mail.

-- 
    Jan Hidders

  .---------------------------------------------------------------------.
  | Post-doctoral researcher               e-mail: jan.hidders@ua.ac.be |
  | Dept. Math. & Computer Science         tel: (+32) 3 218 08 73       |
  | University of Antwerp                  fax: (+32) 3 218 07 77       |
  | Middelheimlaan 1, BE-2020 Antwerpen, BELGIUM     room: G 3.21       |
  `---------------------------------------------------------------------'
Received on Wednesday, 24 September 2003 11:09:54 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 20:17:16 UTC