| r -- mkfs(class, ty, fieldvar) ' ∈ st, okval(val, ty), r ∈ st, okval(st[r -- mkfs(class, ty, fieldvar) '], ty) ⊦ mkfs(class, ty, fieldvar) ' = _type, goodfieldandtype(r0, sk0, st[r -- mkfs(class, ty, fieldvar) ', val]) ↔ goodfieldandtype(r0, sk0, st) |
⊦ is_fskey(sk) → (goodfieldandtype(r, sk, st) ↔ r -- sk ∈ st ∧ okval(st[r -- sk], sk .fs .type))
⊦ is_indexkey(sk) → ¬ goodfieldandtype(r, sk, st)
is_fskey(sk0), r -- mkfs(class, ty, fieldvar) ' ∈ st, okval(val, ty), r ∈ st, okval(st[r -- mkfs(class, ty, fieldvar) '], ty) ⊦ mkfs(class, ty, fieldvar) ' = _type, r0 -- sk0 ∈ st[r -- mkfs(class, ty, fieldvar) ', val] ∧ okval(st[r -- mkfs(class, ty, fieldvar) ', val][r0 -- sk0], sk0 .fs .type) ↔ goodfieldandtype(r0, sk0, st)
[[CONCRETESIMPRULES : ([CSIMPSEQ : ⊦ ¬ is_fskey(sk) ↔ is_indexkey(sk)])], [EXTRATERMS : (st[r -- mkfs(class, ty, fieldvar) ', val], sk0, r0)]]