{α : Type u} →
  {cmp : α → α → Ordering} →
    {motive : Std.LawfulEqCmp cmp → Sort u_1} →
      ([toReflCmp : Std.ReflCmp cmp] → (eq_of_compare : ∀ {a b : α}, cmp a b = Ordering.eq → a = b) → motive ⋯) →
        (t : Std.LawfulEqCmp cmp) → motive t