| ⊦ sk = sk0, (st[r -- sk, val][r0 -- sk0, val0]) = (st[r0 -- sk0, val0][r -- sk, val]) |
⊦ rk ≠ rk0 → (st[rk0, val][rk, val0]) = (st[rk, val0][rk0, val])
[[CONCRETESIMPRULES : ([CSIMPSEQ : ⊦ r -- sk = r0 -- sk0 ↔ r = r0 ∧ sk = sk0])], [EXTRATERMS : (val0, r0 -- sk0, val, r -- sk, st)]]