[PHP] Pull namespace prefix into global scope

using.php

<?php

function using($ns) {
  static $ns_cache = [];
  $ns = trim($ns, '\\');
  if (empty($ns_cache[$ns])) {
    return spl_autoload_register($ns_cache[$ns] = function($class) use ($ns) {
      return class_exists("$ns\\$class", false) && class_alias("$ns\\$class", $class, true);
    }, true, false);
  } else return false;
}


/* ***************
 * EXAMPLE
 * ***************
 
namespace Foo\Bar {
  class Baz {
    public static function lol(){ 
      echo "kek";
    }
  }
}

namespace {
  using("Foo\\Bar");
  Baz::lol();
}

// kek

*/