(motive : Option (Lean.Expr × Lean.Expr × Lean.Expr) → Sort u_1) →
  (x : Option (Lean.Expr × Lean.Expr × Lean.Expr)) →
    ((σs H T : Lean.Expr) → motive (some (σs, H, T))) →
      ((x : Option (Lean.Expr × Lean.Expr × Lean.Expr)) → motive x) → motive x