title: Is the R before string cross-platform
body: <p>From <a href="https://msdn.microsoft.com/en-us/magazine/dn519920.aspx" rel="nofollow">MSDN</a>, this code is used in order to match regular expression:</p>
  
  <pre><code>if (regex_match(s, m, regex { R"((\w+) (\w+))" }))
  {
  }
  </code></pre>
  
  <p>Is using the R before the string quota a standard C++?</p>