{α : Type u} →
  [inst : LT α] →
    [inst_1 : LE α] →
      {motive : Std.LawfulOrderLT α → Sort u_1} →
        ((lt_iff : ∀ (a b : α), a < b ↔ a ≤ b ∧ ¬b ≤ a) → motive ⋯) → (t : Std.LawfulOrderLT α) → motive t