closure

<xs:attribute name="closure" default="closed">
  <xs:simpleType>
    <xs:restriction base="xs:string">
      <xs:enumeration value="closed"/>
      <xs:enumeration value="open"/>
      <xs:enumeration value="open-closed"/>
      <xs:enumeration value="closed-open"/>
    </xs:restriction>
  </xs:simpleType>
</xs:attribute>