php__phplib/apps/autoload_magic.php

<?php
/**
 * Demonstrate using autoload_except() to avoid fatals with PSR0/4 autoloaders.
 */

require __DIR__ . '/../misc/psr0.php';

spl_autoload_register('autoload_except');

try {
  $x = new Zoo();
}
catch (Exception $e) {
  echo "We did not get a fatal when instantiating a nonexistent class.\n";
  die($e->getMessage() . PHP_EOL);
}