| rk0 ∈ st ↔ rk0 ∈ st0, st[r0 -- sk] = st0[r0 -- sk], rk ∈ st, ∀ r0, sk. r0 ≠ r → st[r0 -- sk] = st0[r0 -- sk], r -- _type ∈ st → st[r -- _type] = st0[r -- _type], r -- _length ∈ st → st[r -- _length] = st0[r -- _length], ∀ rk. rk ∈ st ↔ rk ∈ st0 ⊦ (st -- rk)[r0 -- sk] = (st0 -- rk)[r0 -- sk], r0 = r |
⊦ rk ≠ rk0 → (st -- rk0)[rk] = st[rk]
⊦ ∅[rk] = noval
[[CONCRETESIMPRULES : ([CSIMPSEQ : ⊦ (st -- rk)[rk] = ∅[rk]], [CSIMPSEQ : ⊦ rk ≠ rk0 → (st -- rk0)[rk] = st[rk]])], [EXTRATERMS : (r0 -- sk, rk, st)]]