For every state, there is a set of outgoing transitions, of which no more than one will fire. The order of evaluation of transitions is determined by the following:
•Outgoing transitions belonging to the given region and with triggers.
•The transitions must retain their order in vertex's outgoing transitions list.
•External compound transitions with triggers outgoing from enclosed states.
•Outgoing transitions belonging to the given region and without triggers.
•The transitions must retain their order in vertex's outgoing transitions list.
•External compound transitions without triggers outgoing from enclosed states (for non-simple states).