If the incoming edge is a ControlFlow, then all outgoing edges shall be ControlFlows and, if the incoming edge is an ObjectFlow, then all outgoing edges shall be ObjectFlows. Source Unified Modeling Language 2.5.1
ValuePin – Value pins are excluded from fUML because they are redundant with using value specifications to specify values. Source Semantics of a Foundational Subset for Executable UML Models 1.4
Variables are excluded from fUML because the passing of data between actions can be achieved using object flows. Source Semantics of a Foundational Subset for Executable UML Models 1.4
The sole mechanism for asynchronous invocation in fUML is via send signal action. This can be used to achieve the effect of broadcasting and sending objects. Source Semantics of a Foundational Subset for Executable UML Models 1.4
