| fid ∈ fs ⊦ ∃ fs0. (∀ fid0. fid0 ∈ fs0 ↔ fid0 = fid) ∧ (∀ fid. fid ∈ fs0 → fs0[fid] = fs[fid]), (∀ fid0. fid0 ∈ (∅)[fid, fs[fid]] ↔ fid0 = fid) ∧ (∀ fid0. fid0 ∈ (∅)[fid, fs[fid]] → (∅)[fid, fs[fid]][fid0] = fs[fid0]) |
fid ∈ fs, fid0 ∈ (∅)[fid, fs[fid]] ⊦ (∅)[fid, fs[fid]][fid0] = fs[fid0], ∃ fs0. (∀ fid0. fid0 ∈ fs0 ↔ fid0 = fid) ∧ (∀ fid. fid ∈ fs0 → fs0[fid] = fs[fid])
Used simplifier rules: ⊦ fid ∈ fs[fid, f]; (s)% ⊦ ¬ fid ∈ ∅; (s)% ⊦ fid ≠ fid0 → (fid ∈ fs[fid0, f] ↔ fid ∈ fs); (s)