title: PHP regular expressions: No ending delimiter '^' found in
body: <p>I've been having some trouble with regular expressions.</p>
  
  <p>This is my code </p>
  
  <pre><code>$pattern = "^([0-9]+)$";
  
  if (preg_match($pattern, $input))
     echo "yes";
  else
     echo "nope";
  </code></pre>
  
  <p>I run it and get:</p>
  
  <blockquote>
    <p>Warning: preg_match() [function.preg-match]: No ending delimiter '^' found in </p>
  </blockquote>