| ∀ str, r, refs0, ty0, st, ty. validrefs(str, r ' + refs0, ty0, st) ∧ validrefs(str, acc + r ', ty, st) → validrefs(str, acc + r ' + refs0, ty, st), validrefs(str, r ' + refs0, ty0, st), validrefs(str, (r0 + acc) + r ', ty, st) ⊦ validrefs(str, (r0 + acc) + r ' + refs0, ty, st) |
validrefs(str, r ' + refs0, ty0, st), validrefs(str, (r0 ' + acc) + r ', ty, st), ∀ str, r, refs0, ty0, st, ty. validrefs(str, r ' + refs0, ty0, st) ∧ validrefs(str, acc + r ', ty, st) → validrefs(str, acc + r ' + refs0, ty, st) ⊦ validrefs(str, (r0 ' + acc) + r ' + refs0, ty, st)
[[CONCRETESIMPRULES : ([CSIMPSEQ : ⊦ r + refs = r ' + refs])]]