The backward-forward type is used to specify repeat directions. The start of the repeat has a forward direction while the end of the repeat has a backward direction.
<xs:simpleType name="backward-forward"><xs:annotation><xs:documentation>The backward-forward type is used to specify repeat directions. The start of the repeat has a forward direction while the end of the repeat has a backward direction.</xs:documentation></xs:annotation><xs:restriction base="xs:token"><xs:enumeration value="backward"/><xs:enumeration value="forward"/></xs:restriction></xs:simpleType>