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RE: Restricting substitution groups?

From: Mark Feblowitz <mfeblowitz@frictionless.com>
Date: Mon, 11 Feb 2002 14:17:36 -0500
Message-ID: <4DBDB4044ABED31183C000508BA0E97F040AB876@fcpostal.frictionless.com>
To: "'Martin Gudgin'" <marting@develop.com>
Cc: "Xmlschema-Dev (E-mail)" <xmlschema-dev@w3.org>
Here's a minor improvement. 

Thanks, again

Mark




----------------------------------------------------------------------------
----
 
Mark Feblowitz                                   [t] 617.715.7231
Frictionless Commerce Incorporated     [f] 617.495.0188 
XML Architect                                     [e]
mfeblowitz@frictionless.com
400 Technology Square, 9th Floor 
Cambridge, MA 02139 
www.frictionless.com  
 

-----Original Message-----
From: Martin Gudgin [mailto:marting@develop.com]
Sent: Friday, February 08, 2002 3:20 AM
To: Mark Feblowitz
Cc: Xmlschema-Dev (E-mail)
Subject: Re: Restricting substitution groups?

I use the jscript at[1]. It's functional, at least.

Martin

[1] http://marting.develop.com/xsd/xsdms.js



----- Original Message -----
From: "Mark Feblowitz" <mfeblowitz@frictionless.com>
To: "'Martin Gudgin'" <marting@develop.com>
Cc: "Xmlschema-Dev (E-mail)" <xmlschema-dev@w3.org>
Sent: Thursday, February 07, 2002 6:15 PM
Subject: RE: Restricting substitution groups?


> What do you use to validate with MSXML 4? Is there particular VB or
> javascript that you use?
>
> I know it sounds old-fashioned, but I sure wish there was a command line
> executable for me to run.
>
> Of course, better yet would be a full interactive development environment.
> XML Spy uses its own validating parser (even though it uses MSXML for its
> XSL processing).
>
> Any pointers would be appreciated.
>
> Mark
>
> --------------------------------------------------------------------------
--
> ----
>
> Mark Feblowitz                                   [t] 617.715.7231
> Frictionless Commerce Incorporated     [f] 617.495.0188
> XML Architect                                     [e]
> mfeblowitz@frictionless.com
> 400 Technology Square, 9th Floor
> Cambridge, MA 02139
> www.frictionless.com
>
>
> -----Original Message-----
> From: Martin Gudgin [mailto:marting@develop.com]
> Sent: Thursday, February 07, 2002 5:47 AM
> To: Eric van der Vlist; xmlschema-dev@w3.org
> Subject: Re: Restricting substitution groups?
>
> Eric,
>
> My take on this is that it is OK.
>
> The table shown under Particle Valid: Restriction could be said to be
> misleading as it forbids base of element and derived of choice. Perhaps
one
> way of thinking about it is that the element ref is in fact a ref to a
> choice group rather than an element decl and hence corresponds to a choice
> particle. However, I agree that Clause 2 of RecurseLax[1] is problematic
in
> this case.
>
> Sounds to me like the easiest fix is to say, when the choice your
> restricting is in fact a synthetic choice due to a substitution group then
> the order rule does not apply.
>
> I note that Xerces 1.4.4 and MSXML 4.0 both deal with your schema ( and
> instance crufted up by me ) perfectly well.
>
> Gudge
>
> [1] http://www.w3.org/TR/xmlschema-1/#rcase-RecurseLax
>
> ----- Original Message -----
> From: "Eric van der Vlist" <vdv@dyomedea.com>
> To: <xmlschema-dev@w3.org>
> Sent: Thursday, December 06, 2001 4:38 PM
> Subject: Restricting substitution groups?
>
>
> > Given that a substitution group is kind of equivalent to xs:choice:
> >
> > http://www.w3.org/TR/xmlschema-1/#cos-particle-restrict
> >
> >
> > 2.1 Any top-level element declaration particle (in R or B) which is the
> > {substitution group affiliation} of one or more other element
> > declarations is treated as if it were a choice group whose {min occurs}
> > and {max occurs} are those of the particle, and whose {particles}
> > consists of one particle with {min occurs} and {max occurs} of 1 for the
> > top-level element declaration and for each of the declarations in its
> > ·substitution group·.
> >
> > Does that mean that we can restrict substitution groups?
> >
> > If for instance I have:
> >
> > <xs:element name="head"/>
> > <xs:element name="a" substitutionGroup="head"/>
> > <xs:element name="b" substitutionGroup="head"/>
> > <xs:element name="c" substitutionGroup="head"/>
> >
> > and:
> >
> > <xs:complexType name="base">
> >   <xs:sequence>
> >     <xs:element ref="head"/>
> >   </xs:sequence>
> > </xs:complexType>
> >
> > is
> >
> > <xs:complexType name="derived">
> >   <xs:complexContent>
> >    <xs:restriction base="base">
> >     <xs:sequence>
> >       <xs:choice>
> >         <xs:element ref="a"/>
> >         <xs:element ref="b"/>
> >       </xs:choice>
> >     </xs:sequence>
> >    </xs:restriction>
> >   </xs:complexContent>
> > </xs:complexType>
> >
> > a valid restriction?
> >
> > I guess not since it doesn't seem to match the condition for restricting
> > choices:
> >
> > Schema Component Constraint: Particle Derivation OK (Choice:Choice --
> > RecurseLax)
> > For a choice group particle to be a ·valid restriction· of another
> > choice group particle all of the following must be true:
> > 1 R's occurrence range is a valid restriction of B's occurrence range as
> > defined by Occurrence Range OK (§3.9.6);
> > 2 There is a complete ·order-preserving· functional mapping from the
> > particles in the {particles} of R to the particles in the {particles} of
> > B such that each particle in the {particles} of R is a ·valid
> > restriction· of the particle in the {particles} of B it maps to as
> > defined by Particle Valid (Restriction) (§3.9.6).
> > NOTE: Although the ·validation· semantics of a choice group does not
> > depend on the order of its particles, derived choice groups are required
> > to match the order of their base in order to simplify checking that the
> > derivation is OK.
> >
> > The question should then probably be which is the order of the elements
> > of a substitution group when they are mapped to a xs:choice during
> > validation (and how can this be used to restrict a substitution group) ?
> >
> > Thanks
> >
> > Eric
> > --
> > See you in Orlando for XML 2001.
> >
http://www.xmlconference.net/xmlusa/
> > ------------------------------------------------------------------------
> > Eric van der Vlist       http://xmlfr.org            http://dyomedea.com
> > http://xsltunit.org      http://4xt.org           http://examplotron.org
> > ------------------------------------------------------------------------
> >
>



Received on Monday, 11 February 2002 14:18:13 GMT

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