1<grammar xmlns="http://relaxng.org/ns/structure/1.0" > 2 <start> 3 <element name="foo"> 4 <attribute> 5 <choice> 6 <name>alpha</name> 7 <name>bravo</name> 8 </choice> 9 <choice> 10 <value>none</value> 11 <value>all</value> 12 </choice> 13 </attribute> 14 </element> 15 </start> 16</grammar> 17