P5: Guidelines for Electronic Text Encoding and Interchange

<rng:element name="valList">
 <rng:ref name="att.global.attributes"/>
 <rng:optional>
  <rng:attribute name="mode" defaultValue="add">
   <rng:choice>
    <rng:value>add</rng:value>
    <rng:value>delete</rng:value>
    <rng:value>change</rng:value>
    <rng:value>replace</rng:value>
   </rng:choice>
  </rng:attribute>
 </rng:optional>
 <rng:optional>
  <rng:attribute name="type" defaultValue="open">
   <rng:choice>
    <rng:value>closed</rng:value>
    <rng:value>semi</rng:value>
    <rng:value>open</rng:value>
   </rng:choice>
  </rng:attribute>
 </rng:optional>
 <rng:oneOrMore>
  <rng:ref name="valItem"/>
 </rng:oneOrMore>
</rng:element>

element valList
{
   att.global.attributes,
   attribute mode { "add" | "delete" | "change" | "replace" }?,
   attribute type { "closed" | "semi" | "open" }?,
   valItem+
}