| okbytearray(r1, st) ⊦ path∃(str, r, r0, st[r1 -- i ', byteval(by)]) ↔ path∃(str, r, r0, st) |
⊦ path∃(str, r, r0, st) ↔ (∃ refs. refs ≠ [] ∧ refs .first = r ∧ refs .last = r0 ∧ validrefs(str, refs, st[r -- _type] .type, st))
okbytearray(r1, st) ⊦ (∃ refs. refs ≠ [] ∧ refs .first = r ∧ refs .last = r0 ∧ validrefs(str, refs, (st[r1 -- i ', byteval(by)][r -- _type]) .type, st[r1 -- i ', byteval(by)])) ↔ path∃(str, r, r0, st)
[[CONCRETESIMPRULES : ()], [EXTRATERMS : (st[r1 -- i ', byteval(by)], r0, r, str)]]