| fid0 ∈ fs ↔ fid0 ∈ root0.fids ∨ fid0 ∈ ofh.fids, root0[path] = fnode(fid), root0.dir?, fids-cons(root0, fs, ofh), py(user, parent(path), root0, fs), path ∈ root0 ⊦ fid0 ≠ fid ∧ fid0 ∈ fs ↔ fid0 ∈ root0.fids \ {fid} ∨ fid0 ∈ ofh.fids, path = ε, fid ∈ ofh.fids, fid ∈ root0.fids \ {fid} |
Used simplifier rules: ⊦ ¬ fid ∈ fidb → ¬ fid ∈ fidb \ fidb0; (s)% ⊦ fid0 ∈ fidb ∧ fid0 ≠ fid1 → fid0 ∈ fidb \ {fid1} ; (ss) Used formulas: fid0 ∈ fs