Re: Streaming ITS processor

Asgeir Frimannsson wrote:
> On Friday 13 June 2008 22:59:38 Jirka Kosek wrote:
>> Asgeir Frimannsson wrote:
>>> Reading through the ITS spec, it seems like ITS only uses a subset of
>>> xpath, limited to the child and attribute axes (same as xslt patterns).
>> Why you think that ITS uses only XPath subset? You can use full XPath in
>> selectors.
> 
> Let me rephrase that: the spec hints towards the usefulness of limiting the 
> selector attributes to XSLT patterns (which are limited to the child and 
> attribute axes) in Section 2.1.2 (Global Approach). And I guess it seems 
> reasonable to follow this 'recommendation' as many ITS implementations rely on 
> XSLT?

Yes, but XPath patterns as defined in XSLT are not generally streamable. 
Although top-level path components are limited to child, attribute and 
descendant axes, in predicate you can use all axes which actually 
prevents streaming.

E.g.

//chapter[@id = /book/metadata/listofchapterstoreview/chapterid]

-- 
------------------------------------------------------------------
   Jirka Kosek      e-mail: jirka@kosek.cz      http://xmlguru.cz
------------------------------------------------------------------
        Professional XML consulting and training services
   DocBook customization, custom XSLT/XSL-FO document processing
------------------------------------------------------------------
  OASIS DocBook TC member, W3C Invited Expert, ISO JTC1/SC34 member
------------------------------------------------------------------