title: Semicolon in namespace. Necessary?
body: <p>when working with namespace, I need to finish it with a semicolon? When I put a forward declaration of a class into a namespace, for example, many people doesn't include a semicolon but, it seems to be optional.</p>
  
  <p>Does semicolon add functionality or change the current functionality by adding or removing?</p>
  
  <p>Thanks. </p>