Some definitions of interest.
w-E	Def E == {p:(Id)| isnull(a(1of(p);2of(p))) }
w-V	Def V(i;k) == kindcase(k;a.1of(2of(w))(i,a);l,tg.1of(2of(2of(w)))(l,tg))
w-ekind	Def kind(e) == kind(act(e))
w-act	Def act(e) == a(1of(e);2of(e))
w-loc	Def loc(e) == 1of(e)
w-val	Def val(a) == 2of(outr(a))
w-valtype	Def valtype(i;a) == kindcase(kind(a);a.w.TA(i,a);l,tg.w.M(l,tg))
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'}

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