Register autoload of classes in a folder with customizable file naming rule

gistfile1.php

<?php
/**
 * @author dukeofgaming
 * @param string $path The path where the files with the classes are located (1 class per file always)
 * @param function $rule Callback that receives the file name as parameter and returns the class name
 */
function autoloadPath($path,$rule=null){
	$absolute_path = dirname(__FILE__).DS.$path;
	$files = array_filter(
		scandir($absolute_path),
		create_function('$filename','return preg_match(\'/\.php$/\', $filename);')
	);

	$classes = array();
	if($rule === null){

		function class_name($filename){
			if(preg_match('/(.*)\.php$/', $filename, $matches)){
				return $matches[1];
			}
		}

		foreach($files as $file){
			$classes[class_name($file)] = $absolute_path.DS.$file;
		}

	}else{
		foreach($files as $file){
			$classes[$rule($file)] = $absolute_path.DS.$file;
		}
	}

	spl_autoload_register(
		create_function('$class','
			$classes = '.var_export($classes,true).';
			if(array_key_exists($class, $classes)){
				require_once($classes[$class]);
			}
		')
	);
}