title: C++ const keyword - use liberally?
body: <p>In the following C++ functions:</p>
  
  <pre><code>void MyFunction(int age, House &amp;purchased_house)
  {
      ...
  }
  
  
  void MyFunction(const int age, House &amp;purchased_house)
  {
      ...
  }
  </code></pre>
  
  <p>Which is better?</p>
  
  <p>In both, 'age' is passed by value. I am wondering if the 'const' keyword is necessary: It seems redundant to me, but also helpful (as an extra indication the variable will not be changing).</p>
  
  <p>Does anyone have any opinion as to which (if any) of the above are better?</p>