#pragma once

template <class Derived, class Other = Derived>
struct TotalOrdering
{
  friend constexpr bool operator!=(const Derived &a, const Other &b)
  {
    return !(a == b);
  }

  friend constexpr bool operator<=(const Derived &a, const Other &b)
  {
    return a < b || a == b;
  }

  friend constexpr bool operator>(const Derived &a, const Other &b)
  {
    return !(a <= b);
  }

  friend constexpr bool operator>=(const Derived &a, const Other &b)
  {
    return !(a < b);
  }
};