title: Why does var_dump show filename and line number?
body: <p>Just recently var_dump() in PHP (currently using 5.6.23) started to print out the filename as well as the line number before actually dumping my variable. I'm not aware of any major changes on the server, so I was wondering why this happens, also there's nothing to be found on the web or in the PHP-documentation (<a href="http://php.net/manual/en/function.var-dump.php" rel="noreferrer">var_dump()</a>)</p>
  
  <p>The strange behaviour also happens when using the command line:</p>
  
  <pre><code> &gt; php -r 'var_dump("lol");'
   Command line code:1:
   string(3) "lol"
  </code></pre>
  
  <p>While I'm just used to "string(3) "lol"" being printed.</p>
  
  <p>This is not a showstopper but broke a couple of my unit-tests where I needed to compare some output from an API which is printed using var_dump().
  I first thought it could be related to xdebug, but couldn't find any directive that seemd to be related to this problem.</p>
  
  <p>Any hint what is causing this is appreciated.</p>