Union types

Some phone numbers can be 0800-7663 or 0800-SOME. This requires a union of two possible restrictions:

  <simpleType name="OnlyNumbers">
    <restriction base="string">
      <pattern value="\d{4}-\d{4}"/>
    </restriction>
  </simpleType>
  <simpleType name="NumbersAndNames">
    <restriction base="string">
      <pattern value="\d{4}-[A-Z]{4}"/>
    </restriction>
  </simpleType>
  <simpleType name="Number">
    <union memberTypes="OnlyNumbers NumbersAndNames"
  </simpleType>