token_get_all

<?php
  $tokens = token_get_all('<?'); // => array(array(T_OPEN_TAG, '<?'));
  $tokens = token_get_all('<? echo; ?>'); /* => array(
                                                    array(T_OPEN_TAG,'<?'), 
                                                    array(T_ECHO, 'echo'),
                                                    ';',
                                                    array(T_CLOSE_TAG, '?>') ); */

/* Note in the following example that the string is parsed as T_INLINE_HTML
   rather than the otherwise expected T_ML_COMMENT.
   This is because no open/close tags were used in the "code" provided.
   This would be equivalent to putting a comment outside of <? ?> tags in a normal file. */
  $tokens = token_get_all('/* comment */'); // => array(array(T_INLINE_HTML, '/* comment */'));
?>