| acc = [], validrefs(str, r ' + acc, ty, st), validrefs(str, (r ' + acc) .last ' + refs1, ty0, st), ∀ str, ty, st, refs1, ty0. validrefs(str, acc, ty, st) ∧ validrefs(str, acc .last ' + refs1, ty0, st) → acc = [] ∨ validrefs(str, acc + refs1, ty, st) ⊦ validrefs(str, (r ' + acc) + refs1, ty, st) |
⊦ validrefs(str, [], ty, st)
validrefs(str, r ', ty, st), validrefs(str, r ' + refs1, ty0, st) ⊦ validrefs(str, r ' + refs1, ty, st)
[[CONCRETESIMPRULES : ([CSIMPSEQ : ⊦ [] + refs = refs], [CSIMPSEQ : ⊦ r ' .last = r], [CSIMPSEQ : ⊦ (refs + refs0) + refs1 = refs + refs0 + refs1], [CSIMPSEQ : ⊦ refs + [] = refs])]]