<xsd:element name="roles">
    <xsd:complexType>
        <xsd:sequence>
            <xsd:element ref="xsf:role" minOccurs="1" maxOccurs="unbounded" />
            <xsd:element ref="xsf:membership" minOccurs="0" maxOccurs="1" />
        </xsd:sequence>
        <xsd:attribute name="default" type="xsd:string" use="required" />
        <xsd:attribute name="initiator" type="xsd:string" use="optional" />
        <xsd:attribute name="hideStatusBarDisplay" type="xsf:xdYesNo" use="optional" />
    </xsd:complexType>
    <!-- role names must be unique -->
    <xsd:unique name="roles_name_unique">
        <xsd:selector xpath="./xsf:role" />
        <xsd:field xpath="@name" />
    </xsd:unique>
    <!-- fields must reference existing role -->
    <xsd:key name="role_name_key">
        <xsd:selector xpath="./xsf:role" />
        <xsd:field xpath="@name" />
    </xsd:key>
    <xsd:keyref name="role_default" refer="xsf:role_name_key">
        <xsd:selector xpath="." />
        <xsd:field xpath="@default" />
    </xsd:keyref>
    <xsd:keyref name="role_initiator" refer="xsf:role_name_key">
        <xsd:selector xpath="." />
        <xsd:field xpath="@initiator" />
    </xsd:keyref>
    <xsd:keyref name="role_membership" refer="xsf:role_name_key">
        <xsd:selector xpath="./xsf:membership/*" />
        <xsd:field xpath="@memberOf" />
    </xsd:keyref>
</xsd:element>