RE: UPA violation or not?

fwiw my version of Apache xmlbeans validate.cmd rejects this 
schema as containing a UPA violation, whereas my .NET 1.1 
xsd.exe command generates a nice little C# class without 
batting an eyelid:

public class bar {

    /// <remarks/>
    [System.Xml.Serialization.XmlElementAttribute("pongo")]
    public string[] pongo;

    /// <remarks/>
    [System.Xml.Serialization.XmlElementAttribute("pongo")]
    public string[] pongo1;
}


Paul


-----Original Message-----
From: xmlschema-dev-request@w3.org
[mailto:xmlschema-dev-request@w3.org]On Behalf Of Michael Kay
Sent: 16 December 2004 00:19
To: xmlschema-dev@w3.org
Subject: UPA violation or not?



Xerces reports this schema as a UPA violation, XSV reckons it is OK. Which
is correct?

<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
	<xs:complexType name="bar">
		<xs:sequence>
		  <xs:element ref="pongo" minOccurs="0" maxOccurs="2"/>
		  <xs:element ref="pongo" minOccurs="0" maxOccurs="2"/>
		</xs:sequence>
  	</xs:complexType>
	<xs:element name="doc" type="bar"/>
	<xs:element name="pongo" type="xs:string"/>
</xs:schema>

Saxon 8.1 reports it as ambiguous, my current build of Saxon 8.2 doesn't (an
unintentional side-effect of an unrelated change). 

My reading of the spec is that it probably is ambiguous, but that it really
doesn't need to be.

Michael Kay