title: find the first occurrence of non-alphanumeric character in a string
body: <p>I know that i could use <code>strpos</code> to find the first occurrence of a string. But is it possible to find the first occurrence of a character that is not an alphabetic character or number.</p>
  
  <p>For example:</p>
  
  <p><code>strpos2('hello world') =&gt; 5</code></p>
  
  <p><code>strpos2('hi!you') =&gt; 2</code></p>