| validrefkeynotnull(str, rk, ty, st) ∧ (∃ st2. st0 ∪ st = st2 ∪ st) → validrefkeynotnull(str, rk, ty, st0 ∪ st) ⊦ validrefkeynotnull(str, rk, ty, st) → validrefkeynotnull(str, rk, ty, st0 ∪ st) |
validrefkeynotnull(str, rk, ty, st) ⊦ validrefkeynotnull(str, rk, ty, st0 ∪ st), ∃ st2. st0 ∪ st = st2 ∪ st
[[CONCRETESIMPRULES : ()]]