- world->item._startup= (test_callback_fn*)world_test_startup;
- world->item.set_pre((test_callback_fn*)world_pre_run);
- world->item.set_flush((test_callback_fn*)world_flush);
- world->item.set_post((test_callback_fn*)world_post_run);
- world->_on_error= (test_callback_error_fn*)world_on_error;