class_alias

namespace tf\users {}

namespace tf\core {

    class collection {
        private $_cl;
        function __construct()  { $this->_cl = get_class($this);  }
        function get_cl()       { return $this->_cl; }
    }

    class core {

        private $_cl;
        function register($name) {

            $from = 'tf\\core\\collection';
            $to =   'tf\\users\\' . $name;

            printf ("aliasing %s --> %s : %s <br/> \n",  $from, $to, class_alias($from, $to)?'OK':'FAIl');

            $a = new $to ();
            $this->_cl = get_class($a);
            return $a;
        }
        function get_cl()       { return $this->_cl; }
    }

}


namespace {
    use tf\core\core;
    $core = new core();
    $test = $core->register('test');
    printf("core: %s, result: %s, get_class: %s <br/>\n", $core->get_cl(), $test->get_cl(), get_class($test));
}

/*
результат:
aliasing tf\core\collection --> tf\users\test : OK
core: tf\core\collection, result: tf\core\collection, get_class: tf\core\collection

ожидал получить:
 tf\users\test
*/