⊦ ¬ newref(jvmref, st)
⊦ newref(r, st) ↔ r ≠ jvmref ∧ (∀ rk. rk ∈ st → rk .ref ≠ r)
rk ∈ st -- rk .ref ⊦ rk .ref = jvmref
[[CONCRETESIMPRULES : ()]]