| st[r -- _type] = st1[r -- _type], r -- _type ∈ st1, junkrefs(str, r ' + refs1, st1[r -- _type] .type, st1), r ∈ st1, ∀ 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) |
⊦ st ⊆ st1 ∧ junkrefs(str, refs, ty, st1) → junkrefs(str, refs, ty, st)
¬ (st ⊆ st1 ∧ junkrefs(str, r ' + refs1, st1[r -- _type] .type, st1)), st[r -- _type] = st1[r -- _type], r -- _type ∈ st1, junkrefs(str, r ' + refs1, st1[r -- _type] .type, st1), r ∈ st1, ∀ 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)
[[CONCRETESIMPRULES : ()], [EXTRATERMS : (st, st1, str, r ' + refs1, st1[r -- _type] .type)]]