title: No clue why extern is not working
body: <p>I'm just testing out how extern works (using MSVC) and I cannot get it to work, no matter what I do:</p>
  
  <pre><code>// Test.h
  int externalint = 10
  
  // Main.cpp
  void main()
  {
    extern int externalint;
    std::cout &lt;&lt; externalint &lt;&lt; std::endl;
    std::cin.ignore();
  }
  </code></pre>
  
  <p>This results in a linking error, even though I defined it in the header. I do not wish to include the header because the way I read it says it can be in another translation unit and does not need to be included. Am I wrong with the way I am reading it or did I write something incorrectly? If I include the header, it works, as it should, even without the extern declaration.</p>