(header ((h) ihello provides) ((sut) end_of_trail_action2 component) ((w) iworld requires))
(state ((h)) ((sut)) ((w) (b . false)))
<external>.h.hello -> ...
... -> sut.h.hello
sut.w.hello -> ...
... -> <external>.w.hello
(state ((h)) ((sut)) ((w) (b . false)))
(trail "h.hello" "w.hello")
(labels "h.hello" "w.world" "w.cruel")
(eligible "w.world" "w.cruel")
