title: Elegant way to copy substring from char* to std::string
body: <p>I have this <code>char*</code>:</p>
  
  <pre><code>char* line = "This is a great day";
  string subLine;
  </code></pre>
  
  <p>I want that <code>subLine</code> will include: <code>is a great</code></p>
  
  <p>(copy from place 5, the next 10 characters).</p>
  
  <p>Is there a way to do that instead of converting the <code>char*</code> to <code>std::string</code>?</p>