| validrefs(str, r ' + refs0, st[r -- _type] .type, st) ⊦ cyclic(str, r, st[jvmref -- sk, val]), ¬ r ∈ refs0 ∧ ¬ dups(refs0) |
⊦ cyclic(str, r, st) ↔ (∃ refs. dups(refs) ∧ refs .first = r ∧ validrefs(str, refs, st[r -- _type] .type, st))
validrefs(str, r ' + refs0, st[r -- _type] .type, st) ⊦ ∃ refs. dups(refs) ∧ refs .first = r ∧ validrefs(str, refs, (st[jvmref -- sk, val][r -- _type]) .type, st[jvmref -- sk, val]), ¬ r ∈ refs0 ∧ ¬ dups(refs0)
[[CONCRETESIMPRULES : ()], [EXTRATERMS : (st[jvmref -- sk, val], r, str)]]