This set of changes reverts ARCHETYPE.uid back to the type HIER_OBJECT_ID, as it is in the spec. The serialisation used here, including in the XML is as a String, which is clearly more efficient than anything else. Note that pure object serialisation (i.e. to the HIER_OBJECT_ID structured tags) is of course possible from a different serialiser.

The next generation openEHR Archetype.xsd should be changed to use String serialisation for this field.