<grammar xmlns=“relaxng.org/ns/structure/1.0”>

<start>
  <ref name="anyElement"/>
</start>

<define name="anyElement">
  <element>
    <anyName/>
    <zeroOrMore>
      <choice>
        <attribute>
          <anyName/>
        </attribute>
        <text/>
        <ref name="anyElement"/>
      </choice>
    </zeroOrMore>
  </element>
</define>

</grammar>