def add_next(subobject, send_events=True, duplicating=None, moving=None,
    registry=None):
    """Add a subobject, naming it automatically, giving it the name
        returned by this folder's ``next_name`` method.  It has the same
        effect as calling :meth:`substanced.folder.Folder.add`, but you
        needn't provide a name argument.

        This method returns the name of the subobject.
        """
