(* Override in extending model *)

ProcessEnabled( stepdefs, s ) == FALSE
ProcessRunning( stepdefs )    == {}     \* Head( stepdefs )
ProcessParameter( stepdefs )  == {}     \* Head( stepdefs )
ProcessesToRun( stepdefs )    == {}     \* Tail( stepdefs )

TickNext( t )   == t + 1                \* advance time (when process start)
InTransaction   == FALSE                \* TRUE when application service running, FALSE when not