title: Why can't I concat 2 const char* to a std::string?
body: <p>I know that the <a href="http://www.cplusplus.com/reference/string/string/operator+/" rel="nofollow noreferrer">operator +</a> for <code>std::string</code> is not overloaded for two <code>const char*</code>. Thus, </p>
  
  <pre><code>std::string str = "Hello" + " World";
  </code></pre>
  
  <p>does not work; Whereas, the following code works perfectly.</p>
  
  <pre><code>std::string hello = "Hello";
  std::string str = hello  + " World";
  </code></pre>
  
  <p>Moreover, static string concatenation (without +operator) works fine as well</p>
  
  <pre><code>std::string str = "Hello" " World";
  </code></pre>
  
  <p>What is the technical reason for not having a <a href="http://www.cplusplus.com/reference/string/string/operator+/" rel="nofollow noreferrer">operator +</a> for two <code>const char*</code>?</p>