<xs:group name="facets">
    <xs:annotation>
        <xs:documentation>
       We should use a substitution group for facets, but
       that's ruled out because it would allow users to
       add their own, which we're not ready for yet.
    </xs:documentation>
    </xs:annotation>
    <xs:choice>
        <xs:element ref="xs:minExclusive" />
        <xs:element ref="xs:minInclusive" />
        <xs:element ref="xs:maxExclusive" />
        <xs:element ref="xs:maxInclusive" />
        <xs:element ref="xs:totalDigits" />
        <xs:element ref="xs:fractionDigits" />
        <xs:element ref="xs:length" />
        <xs:element ref="xs:minLength" />
        <xs:element ref="xs:maxLength" />
        <xs:element ref="xs:enumeration" />
        <xs:element ref="xs:whiteSpace" />
        <xs:element ref="xs:pattern" />
    </xs:choice>
</xs:group>