| 0 ≤ i0, is_fskey(sk) ⊦ sk = _type, sk = _length, st[r -- sk] = (addarray(r, ty, val ' + mklist(initial_value(ty), i→n(i0)), st)[r -- sk]), sk = 0 ' |
⊦ is_fskey(sk) ∧ sk ≠ _length ∧ sk ≠ _type → (addarray(r, ty, vals, st)[r0 -- sk]) = st[r0 -- sk]
[[CONCRETESIMPRULES : ([CSIMPSEQ : ⊦ ¬ is_fskey(sk) ↔ is_indexkey(sk)], [CSIMPSEQ : ⊦ is_indexkey(sk) → ¬ is_fskey(sk)])], [EXTRATERMS : (sk, r, st, val ' + mklist(initial_value(ty), i→n(i0)), ty, r)]]