P5: Guidelines for Electronic Text Encoding and Interchange

<rng:element name="age">
 <rng:ref name="att.global.attributes"/>
 <rng:ref name="att.editLike.attributes"/>
 <rng:ref name="att.datable.w3c.attributes"/>
 <rng:ref name="att.datable.iso.attributes"/>
 <rng:optional>
  <rng:attribute name="value">
   <rng:ref name="data.count"/>
  </rng:attribute>
 </rng:optional>
 <rng:ref name="macro.phraseSeq.limited"/>
</rng:element>

element age
{
   att.global.attributes,
   att.editLike.attributes,
   att.datable.w3c.attributes,
   att.datable.iso.attributes,
   attribute value { data.count }?,
   macro.phraseSeq.limited
}