∀ {α : Type u} {β : α → Type v} {cmp : α → α → Ordering} {m₁ m₂ : Std.DTreeMap.Raw α β cmp} [inst : (k : α) → BEq (β k)]
  [inst_1 : Std.LawfulEqCmp cmp] [Std.TransCmp cmp] [∀ (k : α), LawfulBEq (β k)],
  m₁.WF → m₂.WF → m₁.beq m₂ = true → m₁.Equiv m₂