| ∀ st, r, sk, val. st[r -- (sks0 + sk '), val] = st[st[r -- sks0] .refval -- sk, val] ⊦ sks0 = [], st[st[r -- sk0] .refval -- (sks0 + sk '), val] = st[st[st[r -- sk0] .refval -- sks0] .refval -- sk, val] |
[[CONCRETESIMPRULES : ()], [EXTRATERMS : (st, st[r -- sk0] .refval, sk, val)]]