title: The namespace starts with :: in C++
body: <blockquote>
    <p><strong>Possible Duplicate:</strong><br>
    <a href="https://stackoverflow.com/questions/2053398/whats-the-purpose-of-a-leading-in-a-c-method-call">What&#39;s the purpose of a leading &ldquo;::&rdquo; in a C++ method call</a>  </p>
  </blockquote>
  
  
  
  <p><a href="https://github.com/google/googletest/blob/master/googletest/docs/advanced.md" rel="nofollow noreferrer">This gtest</a> has the example code.</p>
  
  <pre><code>::testing::AssertionResult IsEven(int n) {
    if ((n % 2) == 0)
      return ::testing::AssertionSuccess();
    else
      return ::testing::AssertionFailure() &lt;&lt; n &lt;&lt; " is odd";
  }
  </code></pre>
  
  <p>How does it work? If the namespace is testing, isn't it testing::AssertionResult is the  right usage?</p>