| st[r -- i '] = refval(r0), maxpath(str, r, st) = # refs, 0 < st[r -- _length] .intval, 0 ≤ i, i < st[r -- _length] .intval, is_array(str, r, st), maxpath(str, r, st) ≤ maxpath(str, r0, st), refs ∈ validrefset(str, r, st) ⊦ # validrefset(str, r, st) = 0, validrefset(str, r, st) = ∅, junkref(str, r, st), cyclic(str, r, st) |
⊦ is_valid_ref(str, r, st) → ( refs ∈ validrefset(str, r, st) ↔ refs ≠ [] ∧ refs .first = r ∧ ¬ has_reffield(refs .last, st) ∧ ¬ dups(refs) ∧ validrefs(str, refs, st[r -- _type] .type, st))
is_valid_ref(str, r, st), st[r -- i '] = refval(r0), maxpath(str, r, st) = # refs, 0 < st[r -- _length] .intval, 0 ≤ i, i < st[r -- _length] .intval, is_array(str, r, st), maxpath(str, r, st) ≤ maxpath(str, r0, st), refs ≠ [] ∧ refs .first = r ∧ ¬ has_reffield(refs .last, st) ∧ ¬ dups(refs) ∧ validrefs(str, refs, st[r -- _type] .type, st) ⊦ # validrefset(str, r, st) = 0, validrefset(str, r, st) = ∅, junkref(str, r, st), cyclic(str, r, st)
[[CONCRETESIMPRULES : ([CSIMPSEQ : ⊦ is_array(str, r, st) → is_valid_ref(str, r, st)])], [EXTRATERMS : (st, r, str, refs)]]