⊦ ks = ks0 ↔ (∀ key. key ∈ ks ↔ key ∈ ks0)
Used simplifier rules: datakeys-set: ⊦ key ∈ datakeys(ks, ri) ↔ key ∈ ri ∧ key.data? ∧ inodekey(key.ino) ∈ ks;% ⊦ ¬ key ∈ ∅; (s) Used terms: ∅, datakeys(∅, ri)