:@choice = 1
:h = "h"!script($_)
	if(1)
		*| a
			|-> a
			#p!checkpoint
			*| aa
				|-> aa
			*| ab
				|-> ab
			choice = 1
		*| b
			|-> b
	*| c
		|-> c
	choice = 1

| h:
h!

| h from #p:
h!from(#p)