Hi Michael, thnx again for your information. i went through the discussion appeared on last year's mail archive. yes it seems like xs:override is not fully implemented yet (atleast apart from the patch submitted by Hiranya[1]). According to Noaman[2] there's fair bit of consideration to be done on xs:override acording to the latest xml-schema 1.1 spec as well . Since Mukul and Hiranya started this work i think it would be more appropriate if i write to them as well, describing my intentions of implementing "xs:override" this as a GSoc project for 2010 . May be they'll be willing to mentor me on the project...
[1]https://issues.apache.org/jira/browse/XERCESJ-1341 [2] http://markmail.org/thread/tv3qtoofzya4ts7l#query:+page:1+mid:xckecvw2mwtd3n43+state:results Regards, Udayanga On Tue, Mar 23, 2010 at 10:59 PM, Michael Glavassevich <[email protected]>wrote: > Hi Udayanga, > > udayanga wickramasinghe <[email protected]> wrote on 03/23/2010 > 08:53:14 AM: > > > > Hi Michael, > > Thnx for your helpful feedback on Xerces projects available. Yes i > > do went through Apache proposed projects list under Xerces (i was > > frankly surprised to see SCD this year as well...thought it was > > completed in last year's GSoc) , and wanted to know if there are > > some additional ideas you might have , since most f the proposed > > project appeared to have been undertaken. > > Certainly doesn't have to be limited to what's been posted so far. I can >> think of at least a few other areas (e.g. xml:id [1] and StAX serialization) >> which haven't been tackled yet and possibly other feature requests that have >> been made over the years that are still active in JIRA. You're also welcome >> to come up with your own ideas. > > > > > I think Ishan plans to do the part ,the derivation of a canonical > > SCP , given a shemaComponent,Namespace ctxt and the corresponding > > XSModel . (If you go through his recent posts , he has already > > defined #getCanonicalSCP(XSObject, > > XSModel,NamespaceContext) under the set of interfaces he's going to > > implement) .I'm just curious as to how exactly it's going to be > > worked out...since it's the reverse problem of resolving a SCP > > expression (which IMHO is a bit straightfoward than deriving a SCP > > for a scehma component) , can there be a 1:n correspondence? ie:- > > for a respective schema component on a given XSModel is there a > > possibility for several SCP expressions existing?? > > The canonical path is supposed to uniquely identify the schema component so >> there should be only one such expression. > > > > > Btw among the ideas you have mentioned, i'm interested in the > > implementation of XML Schema 1.1.spec , xs:override(http:// > > www.w3.org/TR/xmlschema11-1/#override-schema). I find it to be very > > interesting and would indeed be a useful addition for Xerces as well. I > would > > very much appreciate if you could please further elaborate on the > > project requirement..ie:- the scope , technical challenges, related > > work that might be useful(i see it is a bit similar to > > xs:redefine..) ,etc , so that i would be able to get a much clear > > idea n get things started.Thnx in advance.... > > Yes, xs:override is similar to xs:redefine except that it allows >> unconstrained replacement of schema components. Given the problems >> implementers and users of XML Schema have had with xs:redefine I would >> expect that once it's available that it would become the recommended way to >> replace schema components. The scope of the project would be to implement >> this feature. There's a discussion [2] from last year that you may find >> helpful, particularly the response from Khaled Noaman on the challenges of >> implementing xs:override. Hiranya [3] (his patch is for a much earlier XML >> Schema 1.1 draft; the spec has changed quite a bit since then so would no >> longer apply), Mukul and Khaled have looked at this before but I don't >> believe anyone has been working on an implementation lately. I believe most >> of the work still needs to be done. >> > > We would welcome the help. > > > -Udayanga > > Thanks. > > [1] https://issues.apache.org/jira/browse/XERCESJ-1113 > [2] http://markmail.org/thread/tv3qtoofzya4ts7l > [3] https://issues.apache.org/jira/browse/XERCESJ-1341 > > > Michael Glavassevich > XML Parser Development > IBM Toronto Lab > E-mail: [email protected] > E-mail: [email protected] > -- http://www.udayangawiki.blogspot.com
