1 <?xml version=
"1.0" encoding=
"ISO-8859-1"?>
2 <xs:schema xmlns:
xs=
"http://www.w3.org/2001/XMLSchema" elementFormDefault=
"unqualified">
4 <xs:element name=
"foo" type=
"baseType"/>
6 <xs:complexType name=
"baseType">
8 <xs:element name=
"bar" type=
"derivedType" minOccurs=
"0"/>
10 <xs:attribute name=
"attrA" type=
"xs:string" use=
"required"/>
13 <xs:complexType name=
"derivedType">
15 <xs:extension base=
"baseType">
16 <xs:attribute name=
"attrB" type=
"xs:string" use=
"required"/>