autoload.php

<?php
spl_autoload_register(function($class){
    $d = DIRECTORY_SEPARATOR;
    // project-specific namespace prefix

    $prefix = "Mvc\\";

    // base directory for the namespace prefix
    // does the class use the namespace prefix?
    $len = strlen($prefix);
    if (strncmp($prefix, $class, $len) !== 0) {
        // no, move to the next registered autoloader
        return false;
    }

    // get the relative class name
    $relative_class = substr($class, $len);

    // replace the namespace prefix with the base directory, replace namespace
    // separators with directory separators in the relative class name, append
    // with .php
    $file = dirname(__FILE__) . $d . str_replace('\\', $d, $relative_class) . '.php';

    // if the file exists, require it
    if (file_exists($file)) {
        require $file;
        return true;
    }
    return false;
});