'Iterate over all child paths of `parent_path` matched by this
selector.  This can contain parent_path itself.'

def select_from(self, parent_path):

    path_cls = type(parent_path)
    is_dir = path_cls.is_dir
    exists = path_cls.exists
    scandir = parent_path._accessor.scandir
    if (not is_dir(parent_path)):
        return iter([])
    return self._select_from(parent_path, is_dir, exists, scandir)
