| r0 ∈ st[r -- sk, val] .refs ⊦ st[r -- sk, val] .refs = ∅, r0 = r, # st[r -- sk, val] .refs = 0, r0 ∈ st .refs |
⊦ r ∈ st .refs ↔ r ∈ st
r0 ∈ st[r -- sk, val] ⊦ st[r -- sk, val] .refs = ∅, r0 = r, # st[r -- sk, val] .refs = 0, r0 ∈ st .refs
[[CONCRETESIMPRULES : ()], [EXTRATERMS : (st[r -- sk, val], r0)]]