1 <element name="root" xmlns="http://relaxng.org/ns/structure/1.0"> 2 <choice> 3 <element name="child"> 4 <attribute name="type"> 5 <value>Foo</value> 6 </attribute> 7 <!-- Define stuff that's only valid when type is "Foo" --> 8 </element> 9 <element name="child"> 10 <attribute name="type"> 11 <value>Bar</value> 12 </attribute> 13 <!-- Define stuff that's only valid when type is "Bar" --> 14 </element> 15 </choice> 16 </element> 17