OPC 10000-4 7.4.4.5: a SimpleAttributeOperand with an empty browsePath denotes the instance of
typeDefinitionId itself, not "nothing to do". A ConditionId operand (typeDefinitionId
ConditionType or a subtype, attributeId NodeId, empty browsePath) resolves to the event's own
condition instance NodeId - this is what every Alarms and Conditions client sends, in both the
select clause (delivery, via extractEventField) and the where clause (evaluation, via
resolveOperand below). FEAT-58 taught the select-clause validation this; both consumers share
this one resolution so they never drift apart again.
Returns undefined when the operand does not match this shape, so the caller falls back to its
normal browsePath resolution.
OPC 10000-4 7.4.4.5: a SimpleAttributeOperand with an empty browsePath denotes the instance of typeDefinitionId itself, not "nothing to do". A ConditionId operand (typeDefinitionId ConditionType or a subtype, attributeId NodeId, empty browsePath) resolves to the event's own condition instance NodeId - this is what every Alarms and Conditions client sends, in both the select clause (delivery, via extractEventField) and the where clause (evaluation, via resolveOperand below). FEAT-58 taught the select-clause validation this; both consumers share this one resolution so they never drift apart again.
Returns undefined when the operand does not match this shape, so the caller falls back to its normal browsePath resolution.