title: constant variables that are used only in one cpp file - where to declare them
body: <p>I have a small project and all its code is in one namespace (multiple files), in certain file I need to use multiple constants.</p>
  
  <p>Only this one file will use those constant variables.</p>
  
  <p>Which one is the right way to go and what's the difference (I'm familiar with static and const but still don't know the difference)</p>
  
  <ol>
  <li>declare static const in the header, define in the source file</li>
  <li>define const in source file in the namespace scope</li>
  <li>define static const in source file in the namespace scope</li>
  </ol>