title: How to fix error: unknown type name ‘namespace’
body: <pre><code>#ifndef UNO_ACTION_ 
  #define UNO_ACTION_
  namespace Uno
  {
  namespace Game
  {
      class Game;
  }
  } // namespace
  
  namespace Uno
  {
  namespace Action
  {
  using ::Uno::Game::Game;
  
  class Action
  {
  public:
      virtual bool isDisposeable() = 0;
      virtual void takeAction(Game* game) = 0;
      virtual ~Action() {}
  };
  
  }
  }
  #endif
  </code></pre>
  
  <p>I compile these code on ubuntu 12.04 and it returns to set of error:</p>
  
  <pre><code>action.h:4:1: error: unknown type name ‘namespace’
  action.h:4:15: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘{’ token
  action.h:8:1: error: unknown type name ‘namespace’
  action.h:8:15: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘{’ token
  </code></pre>
  
  <p>How do I solve these errors?</p>