| ns ∪ elems nx = dom gstore ∪ ginval ⊦ ∀ n. n ∈ elems nx → n ∈ dom gstore ∪ ginval |
ns ∪ elems nx = dom gstore ∪ ginval, n ∈ nx ⊦ n ∈ gstore, n ∈ ginval
Used simplifier rules: elems-def: ⊦ n ∈ elems nx ↔ n ∈ nx;%unc: ⊦ ns ∪ ns0 = ns0 ∪ ns; from specification set-union[nat-set]%una: ⊦ (ns ∪ ns0) ∪ ns1 = ns ∪ ns0 ∪ ns1; from specification set-union[nat-set]% ⊦ n ∈ dom gstore ↔ n ∈ gstore; (s)% ⊦ n ∈ ns ∪ ns0 ↔ ¬(¬ n ∈ ns ∧ ¬ n ∈ ns0); (ss)