Some definitions of interest.
w-action	Def Action(i) == action(w-action-dec(w.TA;w.M;i))
world	Def World Def == T:IdIdType Def == TA:IdIdType Def == M:IdLnkIdType Def == (i:Id(x:IdT(i,x)))(i:Idaction(w-action-dec(TA;M;i))) Def == (i:Id({m:Msg(M)| source(mlnk(m)) = i } List))Top
	Thm* World  Type{i'}
IdLnk	Def IdLnk == IdId
	Thm* IdLnk  Type
w-isrcvl	Def isrcv(l;a) == isnull(a)isrcv(kind(a))lnk(kind(a)) = l
Id	Def Id == Atom
	Thm* Id  Type
isrcv	Def isrcv(k) == isl(k)
	Thm* k:Knd. isrcv(k)
w-isnull	Def isnull(a) == isl(a)
w-kind	Def kind(a) == 1of(outr(a))

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