I was exchanging messages with a counterparty and we couldn’t agree on the meaning of an optional element. The element is //element(*, Trade)/documentation. It is an optional element. What does it mean when the field is present or not present? Is it: – Whether it is known or not by the sender? – Whether it matters or not? – Whether it exists or not? – Whether is it implicit or not? – etc. We couldn’t find a definition in the documentation of what it meant. What does it mean? Does this apply to all optional elements? Should they be defined? 🙂
