Hello

I want to reference a simple sequence into a more complex UML sequence diagram.

(As in: "Starting in UML 2 the "Interaction Occurrence" element was introduced. The addition of interaction occurrences is arguably the most important innovation in UML 2 interactions modeling. Interaction occurrences add the ability to compose primitive sequence diagrams into complex sequence diagrams. With these you can combine (reuse) the simpler sequences to produce more complex sequences. This means that you can abstract out a complete and possibly complex sequence as a single conceptual unit." See: https://www.ibm.com/developerworks/rational/library/3101.html for this text in context.)

My idea was to simply draw a box using a notation like this one:

sequence diagram name[(arguments)] [: return value]

I would need a loop box to create the reference however the loop box acts as a frame: all elements behind it are visible. The point is to have the box referencing the simpler sequence float in front of the other shapes. A package box will do the trick but this is not the right shape for a reference in UML 2.

Am I missing something or is there no shape available in LucidChart that is intended for referencing other diagrams?