46 lines
1.5 KiB
Python
46 lines
1.5 KiB
Python
# Copyright 2009-2022 Joshua Bronson. All rights reserved.
|
|
#
|
|
# This Source Code Form is subject to the terms of the Mozilla Public
|
|
# License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
|
|
|
|
|
|
"""Functions for iterating over items in a mapping."""
|
|
|
|
from __future__ import annotations
|
|
from operator import itemgetter
|
|
import typing as t
|
|
|
|
from ._typing import KT, VT, ItemsIter, MapOrItems
|
|
|
|
|
|
def iteritems_mapping_or_iterable(arg: MapOrItems[KT, VT]) -> ItemsIter[KT, VT]:
|
|
"""Yield the items in *arg* based on whether it's a mapping."""
|
|
yield from arg.items() if isinstance(arg, t.Mapping) else arg
|
|
|
|
|
|
def iteritems(__arg: MapOrItems[KT, VT], **kw: VT) -> ItemsIter[KT, VT]:
|
|
"""Yield the items from *arg* and then any from *kw* in the order given."""
|
|
yield from iteritems_mapping_or_iterable(__arg)
|
|
yield from kw.items() # type: ignore [misc]
|
|
|
|
|
|
swap = itemgetter(1, 0)
|
|
|
|
|
|
def inverted(arg: MapOrItems[KT, VT]) -> ItemsIter[VT, KT]:
|
|
"""Yield the inverse items of the provided object.
|
|
|
|
If *arg* has a :func:`callable` ``__inverted__`` attribute,
|
|
return the result of calling it.
|
|
|
|
Otherwise, return an iterator over the items in `arg`,
|
|
inverting each item on the fly.
|
|
|
|
*See also* :attr:`bidict.BidirectionalMapping.__inverted__`
|
|
"""
|
|
invattr = getattr(arg, '__inverted__', None)
|
|
if callable(invattr):
|
|
inv: ItemsIter[VT, KT] = invattr()
|
|
return inv
|
|
return map(swap, iteritems_mapping_or_iterable(arg))
|