SYSML17 — Need constraint for inverted provided/required Interfaces (InterfaceRealization and Usage) on ~InterfaceBlock

SysML-1.6 supports Interfaces provided/required (InterfaceRealization and Usage) by a Block, including an InterfaceBlock.

Given that UML-style Port conjugation is not supported in SysML-1.6, a mechanism for inversion of provided/required Interfaces is needed.

While Figure D.19 does not show the Port types, it does show provided/required Interfaces on Ports, and it is implied by other diagrams in the sample problem that those Ports that have inverted provided/required Interfaces are typed by ~InterfaceBlocks.

A constraint should be added to 9.3.2.15 ~InterfaceBlock corresponding to the inversion of any required/provided Interfaces on the original InterfaceBlock.