SYSML17 — 7_composition_acyclic wrong

I agree with this that this should be the intent... "Within an instance of a SysML Block, the instances of properties with composite aggregation shall form an acyclic graph"... but I believe the OCL statement restricts the types and not the instances... I will give an example... it should restrict an instance from being a part of itself... but is should not restrict a Type having a part of the same type (which I believe this does)... take for example something that says System has a composition to itself whose navigation end is named "subSystem"... this says that a System can contain other Systems as a part "subsystem"... this should be legal... but a system1:System cannot contain itself as a subsystem of itself... that should be illegal... I believe that your constraint, constrains the Type (which it should not) and therefore the instance... but it should only constrain the instance and not the type...