| st[r -- _type] = st1[r -- _type], r ∈ st1, junkrefs(str, r ' + refs1, st1[r -- _type] .type, st1), r -- _type ∈ st1, rk ∈ st, ∀ rk. rk ∈ st → rk ∈ st1 ∧ st[rk] = st1[rk] ⊦ junkrefs(str, r ' + refs1, st1[r -- _type] .type, st), ∃ refs. refs ≠ [] ∧ refs .first = r ∧ junkrefs(str, refs, st[refs .first -- _type] .type, st), rk ∈ st1 ∧ st[rk] = st1[rk] |
[[CONCRETESIMPRULES : ([CSIMPSEQ : ⊦ (refs + refs0) + refs1 = refs + refs0 + refs1])], [EXTRATERMS : (rk)]]