Camelize and Decamelize

gistfile1.php

<?php

function decamelize($word) {
  $word = preg_replace_callback (
    '/([A-Z])/', 
    function($matches){
      return strtolower('_' . $matches[0]);
    },
    $word 
  );
  return trim($word, '_');
}

function camelize($word) { 
  return preg_replace_callback (
    '/(_)([a-z])/', 
    function($matches){
      return strtoupper($matches[2]);
    },
    $word 
  );
}