title: Ruby class with static method calling a private method?
body: <p>I have a class with a number of static methods.  Each one has to call a common method, but I'm trying not to expose this latter method.  Making it private would only allow access from an own instance of the class?  Protected does not seem like it would solve the problem here either.</p>
  
  <p>How do I hide do_calc from being called externally in a static context?  (Leaving it available to be called from the first two static methods.)</p>
  
  <pre><code>class Foo
    def self.bar
      do_calc()
    end
    def self.baz
      do_calc()
    end
    def self.do_calc
    end
  end
  </code></pre>