gistfile1.txt

<?php

namespace Alpha {

    class A
    {
        public function hello()
        {
            $b = new \Beta\B;
            $b->world();
        }
    }
}

namespace Beta {

    class B
    {
        public function world()
        {
            echo __NAMESPACE__;
        }
    }
}

namespace {
    $a = new \Alpha\A;
    $a->hello();
}