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In an attempt to redeem myself... Following on from Michael Kay's comments, when using XSD1.0, the only real way to do it is declare your restricted schema to have the same target namespace as the Base schema. I think one way to get around this is to define a 'wrapper' schema and then xs:include your Base and Restricted namespace within it, e.g.: <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns="http://www.example.org/Base" targetNamespace="http://www.example.org/Base" elementFormDefault="qualified"> <xs:include schemaLocation="Base.xsd"/> <xs:include schemaLocation="Restricted.xsd"/> </xs:schema> then both have: <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns="http://www.example.org/Base" targetNamespace="http://www.example.org/Base" elementFormDefault="qualified"> Alternatively you could make E1 and E2 as global elements in the Base namespace, but leave the rest in the Restricted namespace and do: <xs:restriction base="base:AType"> <xs:sequence> <xs:element ref="base:E1"/> <xs:element ref="base:E2"/> </xs:sequence> </xs:restriction> HTH, Pete Cordell Codalogic Ltd Interface XML to C++ the easy way using C++ XML data binding to convert XSD schemas to C++ classes. Visit http://codalogic.com/lmx/ or http://www.xml2cpp.com for more info ----- Original Message ----- From: "Toby Considine" <Toby.Considine@gmail.com> To: <xml-dev@lists.xml.org> Sent: Friday, March 16, 2012 6:01 PM Subject: RE: Unqualified forms and Inheritance by Restriction This seems to argue that the tools that "accept" what I am doing now, do so in error. Which I had an uneasy feeling they did. >>Because the element declaration isn't global, the only way you can replace it with a different element declaration of the same name is by putting that declaration in a schema >>document whose target namespace is {Base}. How would I do this? I tried several variants on <xs:restriction base="base:AType"> <xs:sequence> <xs:element name="base:E1" type="xs:string" fixed="foo"/> <xs:element name="base:E2"> <xs:simpleType> <xs:restriction base="xs:token"> <xs:enumeration value="fie"/> <xs:enumeration value="foe"/> </xs:restriction> </xs:simpleType> </xs:element> </xs:sequence> </xs:restriction> And they failed the same, even when I went so far as to make E1 and E2 root elements in base. At this point I am trying to create valid XML by the infinite monkey approach. http://en.wikipedia.org/wiki/Infinite_monkey_theorem tc _____ "If something is not worth doing, it`s not worth doing well" - Peter Drucker _____ Toby Considine TC9, Inc TC Chair: oBIX & WS-Calendar TC Editor: EMIX, EnergyInterop U.S. National Inst. of Standards and Tech. Smart Grid Architecture Committee Email: <mailto:Toby.Considine@fac.unc.edu> Toby.Considine@g... Phone: (919)619-2104 http://www.tcnine.com/ blog: www.NewDaedalus.com From: Michael Kay [mailto:mike@saxonica.com] Sent: Friday, March 16, 2012 10:53 AM To: xml-dev@lists.xml.org Subject: Re: Unqualified forms and Inheritance by Restriction The issue here is that if element {Base}E1 is mandatory in the base type, it's not good enough to have an element {Restricted}E1 in its place in the derived type: the elements must have the same name. Because the element declaration isn't global, the only way you can replace it with a different element declaration of the same name is by putting that declaration in a schema document whose target namespace is {Base}. XSD 1.1 solves this by allowing you to specify targetNamespace as an attribute on a local element declaration. In 1.0, though, there's no alternative to putting the restricted type in a schema document for the {Base} namespace -- even if this means tresspassing on someone else's namespace. Michael Kay Saxonica On 16/03/2012 13:47, Toby Considine wrote: I have a family of schemas for energy markets that are derived from a root abstract schema. In most cases, the derived types extend the abstract types by adding additional elements. This inheritance by addition is straight-forward. For one key abstract type, I use inheritance by restriction. Derived types must have all the elements of the root type, but they may be restricted to a few enumerated values. Consider the following, simplified and stripped down: Root Schema: <xs:schema xmlns:xs= <http://www.w3.org/2001/XMLSchema> "http://www.w3.org/2001/XMLSchema" xmlns= <VIPRE Anti-phishing found a known bad URL in your email message. It was deleted or quarantined, depending on your settings, and replaced with this message. The anti-phishing setting is located in File>Settings under the Email Protection tab.> "VIPRE Anti-phishing found a known bad URL in your email message. It was deleted or quarantined, depending on your settings, and replaced with this message. The anti-phishing setting is located in File>Settings under the Email Protection tab." targetNamespace= <VIPRE Anti-phishing found a known bad URL in your email message. It was deleted or quarantined, depending on your settings, and replaced with this message. The anti-phishing setting is located in File>Settings under the Email Protection tab.> "VIPRE Anti-phishing found a known bad URL in your email message. It was deleted or quarantined, depending on your settings, and replaced with this message. The anti-phishing setting is located in File>Settings under the Email Protection tab." elementFormDefault="qualified"> <xs:element name="A" type="AType"/> <xs:complexType name="AType" abstract="true"> <xs:sequence> <xs:element name="E1" type="xs:string"/> <xs:element name="E2" type="xs:string" /> </xs:sequence> </xs:complexType> Derivative schema <xs:schema xmlns:xs= <http://www.w3.org/2001/XMLSchema> "http://www.w3.org/2001/XMLSchema" xmlns= <VIPRE Anti-phishing found a known bad URL in your email message. It was deleted or quarantined, depending on your settings, and replaced with this message. The anti-phishing setting is located in File>Settings under the Email Protection tab.> "VIPRE Anti-phishing found a known bad URL in your email message. It was deleted or quarantined, depending on your settings, and replaced with this message. The anti-phishing setting is located in File>Settings under the Email Protection tab." xmlns:base= <VIPRE Anti-phishing found a known bad URL in your email message. It was deleted or quarantined, depending on your settings, and replaced with this message. The anti-phishing setting is located in File>Settings under the Email Protection tab.> "VIPRE Anti-phishing found a known bad URL in your email message. It was deleted or quarantined, depending on your settings, and replaced with this message. The anti-phishing setting is located in File>Settings under the Email Protection tab." targetNamespace= <VIPRE Anti-phishing found a known bad URL in your email message. It was deleted or quarantined, depending on your settings, and replaced with this message. The anti-phishing setting is located in File>Settings under the Email Protection tab.> "VIPRE Anti-phishing found a known bad URL in your email message. It was deleted or quarantined, depending on your settings, and replaced with this message. The anti-phishing setting is located in File>Settings under the Email Protection tab." elementFormDefault="qualified"> <xs:import namespace= <VIPRE Anti-phishing found a known bad URL in your email message. It was deleted or quarantined, depending on your settings, and replaced with this message. The anti-phishing setting is located in File>Settings under the Email Protection tab.> "VIPRE Anti-phishing found a known bad URL in your email message. It was deleted or quarantined, depending on your settings, and replaced with this message. The anti-phishing setting is located in File>Settings under the Email Protection tab." schemaLocation="Base.xsd"/> <xs:element name="ARestricted" type="ARestrictedType"/> <xs:complexType name="ARestrictedType" abstract="false"> <xs:complexContent> <xs:restriction base="base:AType"> <xs:sequence> <xs:element name="E1" type="xs:string" fixed="foo"/> <xs:element name="E2"> <xs:simpleType> <xs:restriction base="xs:token"> <xs:enumeration value="fie"/> <xs:enumeration value="foe"/> </xs:restriction> </xs:simpleType> </xs:element> </xs:sequence> </xs:restriction> </xs:complexContent> </xs:complexType> The derivative schema is invalid. In particular, when processed, each element in ARestricted generates the following error: "rcase-NameAndTypeOK.1: The declarations' {name}s and {target namespace}s are not the same: restriction element is <xs:element name="itemDescription"> and base element is <xs:element name="itemDescription">." http://www.w3.org/TR/2004/REC-xmlschema-1-20041028/#rcase-NameAndTypeOK I can avoid the error if I change each of the schemas from elementFormDefault="qualified" to elementFormDefault="unqualified". The derived schema now validates using XML Spy and Liquid XML Studio. When I use the Liquid Technologies code generation tool to create software objects, the objects generate XML that looks like what I want. Here's the question: Should I be looking for some side effect of switching these schemas from qualified to unqualified? Is there some hidden problem I will come upon if I require conforming schemas to be unqualified? I generally prefer "qualified" for the esthetic reason that I like to see explicit type derivations (prefices) in the schema. I do not have a feel for what else may be affected. Thanks tc _____ "You can cut all the flowers but you cannot keep spring from coming." -Pablo Neruda. _____ Toby Considine TC9, Inc TC Chair: oBIX & WS-Calendar TC Editor: EMIX, EnergyInterop U.S. National Inst. of Standards and Tech. Smart Grid Architecture Committee Email: <mailto:Toby.Considine@fac.unc.edu> Toby.Considine@g... Phone: (919)619-2104 http://www.tcnine.com/ blog: www.NewDaedalus.com
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