title: PHP string number concatenation messed up
body: <p>I got some PHP code here:</p>
  <pre><code>&lt;?php
      echo 'hello ' . 1 + 2 . '34';
  ?&gt;
  </code></pre>
  <p>which outputs 234,</p>
  <p>But when I add a number 11 before &quot;hello&quot;:</p>
  <pre><code>&lt;?php
      echo '11hello ' . 1 + 2 . '34';
  ?&gt;
  </code></pre>
  <p>It outputs 1334 rather than 245 (which I expected it to). Why is that?</p>