title: regex for double and single quotes in PHP
body: <p>I'm trying to make a regex that will match the argument for a function in PHP. The only problem is the regex doesn't work, or I'm not escaping it well, since I need both double quotes and single quotes to be matched, depending on what the developer used in code.</p>
  
  <pre><code>fn_name("string");
  fn_name('string');
  </code></pre>
  
  <p>I've made two expressions, one for each case, but I guess that can be done way better.</p>
  
  <pre><code>/fn_name\("(.*?)\"\)/
  /fn_name\('(.*?)\'\)/
  </code></pre>
  
  <p>How do I make that one regex, and escape it properly from this?</p>
  
  <pre><code>preg_match_all('/fn_name\("(.*?)\"\)/', file_get_contents($filename), $out);
  </code></pre>
  
  <p>Thanks.</p>