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Re: Multiple and circular import/include

From: vivek agarwal <vivekorama@gmail.com>
Date: Fri, 4 Mar 2005 12:07:57 +0530
Message-ID: <2ac3993a050303223769206482@mail.gmail.com>
To: Jack Lindsey <tuquenukem@hotmail.com>, bill.michell@bbc.co.uk, rschloss@us.ibm.com
Cc: xmlschema-dev@w3.org

I think I too appreciate circular references and multiple imports now.

Thanks to all.

-Vivek.


On Thu, 03 Mar 2005 22:37:14 -0500, Jack Lindsey <tuquenukem@hotmail.com> wrote:
> I absolutely agree.  However, such recursive element references that span
> files with redundant xs:include/import statements can crash JAXB, as a
> development team politely informed me.  Then I got a taste of my own
> medicine when Spy 2005 SP1 did the same to me.  I just upgraded but to keep
> my developers happy, I am trying a re-modularization of a large schema.
> After all, the customer is always right!
> 
> Cheers Jack
> 
> >From: "Bill Michell" <bill.michell@bbc.co.uk>
> >To: "vivek agarwal" <vivekorama@gmail.com>,        "Bob Schloss"
> ><rschloss@us.ibm.com>
> >CC: <xmlschema-dev@w3.org>
> >Subject: RE: Multiple and circular import/include
> >Date: Thu, 3 Mar 2005 09:32:50 -0000
> >
> >
> >I find them really useful...
> >
> >I have a generic "asset" that can have many types of extension - but any
> >instance of that asset need to be able to contain other assets - either
> >references, or completely embedded inline.
> >
> >The core document contains the basic asset definition but the extensions
> >each live in their own schema - that needs a reference to the core document
> >- which in turn needs a reference to the current collection of extension
> >schemae...
> >
> >In other words elements can be nested recursively so the schema documents
> >need to be able to express that nesting.
> >
> >
> >
> >--
> >Bill Michell
> >Development Team Leader, Broadcast Platforms, BBC News Interactive.
> >
> >
> >
> >-----Original Message-----
> >From: xmlschema-dev-request@w3.org [mailto:xmlschema-dev-request@w3.org] On
> >Behalf Of vivek agarwal
> >Sent: Wednesday, March 02, 2005 9:03 PM
> >To: Bob Schloss
> >Cc: xmlschema-dev@w3.org
> >Subject: Re: Multiple and circular import/include
> >
> >
> >Thanks Bob!
> >But, I still don't understand why the spec allows circular references!? Is
> >there a reason? or is it just like that?
> >
> >Thanks,
> >Vivek.
> >
> >
> >
> >On Tue, 1 Mar 2005 15:17:04 -0500, Bob Schloss <rschloss@us.ibm.com> wrote:
> > >
> > >
> > > Vivek,
> > >
> > >       It is not an error to include the same schema document as the
> > > target of multiple <include> or <import> directives.
> > >
> > >       Circular <include> or <import> directives are permitted.
> > >
> > >       This is my mental model:
> > >
> > > 1. The processor fetches your top-level schema document, and then
> > > keeps fetching any other schemas which are referenced through
> > > directives, transitively, but whenever it sees a directive targetting
> > > something it has already fetched, it doesn't fetch it again.  At the
> > > end of this process, the "actual schema" to be used for processing now
> > > exists in memory, having been merged from 1...n individual documents
> > > having the XML representation of XML Schema.
> > >
> > > 2. Then the processor starts doing whatever it plans to do (validation
> > > of instance documents during parsing, generating Data Binding code,
> > > generating UI forms, or whatever).
> > >
> > >       Because of subtleties associated with <redefine>, for the sanity
> > > of anyone who may have to maintain what you design, I would try to
> > > avoid circular redefines.
> > >
> > >             Good Luck,
> > >             Bob
> > >
> > > Scalable XML Infrastructure
> > > IBM Thomas J Watson Research Center
> > > Yorktown Heights, New York, USA
> > > http://www.research.ibm.com/XML
> > >
> > >              vivek agarwal
> > >              <vivekorama@gmail
> > >              .com>
> >To
> > >              Sent by:                  xmlschema-dev@w3.org
> > >              xmlschema-dev-req
> >cc
> > >              uest@w3.org
> > >
> >Subject
> > >                                        Multiple and circular
> > >              03/01/2005 01:41          import/include
> > >              AM
> > >
> > >              Please respond to
> > >                vivek agarwal
> > >
> > >
> > > Hi,
> > >
> > > I have a question on multiple and circular import/include each, if
> > > somebody could help.
> > >
> > > Is it an error to import/include a schema more than once?
> > > A import/includes B1 and B2.
> > > Both B1, and B2, import/includes C.
> > > What is the expected behaviour of the processor in such a case?
> > >
> > > Are circular import/includes allowed?
> > > A import/includes B, and B import/includes A?
> > > What is the expected behaviour of the processor in such a case?
> > >
> > > Thanks,
> > > Vivek.
> > >
> > >
> >
> >
> >http://www.bbc.co.uk/
> >
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Received on Friday, 4 March 2005 06:38:32 GMT

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