title: C#: How to have an optional parameter referencing another parameter
body: <p>Is that possible for one to have something like this?</p>
  
  <pre><code>public void Foo(Bar someBar, int someBarValues = someBar.aInt){
    //do something
  }
  </code></pre>
  
  <p>or is it literally nonsense as default values must be a runtime constant?
  if that's the case, is there any work around?</p>