"Treebeard exceptions"


class InvalidPosition(Exception):
    "Raised when passing an invalid pos value"


class InvalidMoveToDescendant(Exception):
    "Raised when attemping to move a node to one of it's descendants."


class MissingNodeOrderBy(Exception):
    """
    Raised when an operation needs a missing
    :attr:`~treebeard.MP_Node.node_order_by` attribute
    """


class PathOverflow(Exception):
    """
    Raised when trying to add or move a node to a position where no more nodes
    can be added (see :attr:`~treebeard.MP_Node.path` and
    :attr:`~treebeard.MP_Node.alphabet` for more info)
    """