public bool Equals(Prio <D> that) => Priority == that.Priority;
public bool Equals(Prio <D> that) { return(Priority == that.Priority); }
public int CompareTo(Prio <D> that) => Priority.CompareTo(that.Priority);
public int CompareTo(Prio <D> that) { return(Priority.CompareTo(that.Priority)); }