Class OrderedSet

xarray/core/utils.py:609–648

A simple ordered set. The API matches the builtin set, but it preserves insertion order of elements, like a dict. Note that, unlike in an OrderedDict, equality tests are not order-sensitive.

class OrderedSet(MutableSet[T]):
    """A simple ordered set.

    The API matches the builtin set, but it preserves insertion order of elements, like
    a dict. Note that, unlike in an OrderedDict, equality tests are not order-sensitive.
    """

    _d: dict[T, None]

    __slots__ = ("_d",)

    def __init__(self, values: Iterable[T] | None = None):
        self._d = {}
        if values is not None:
            self.update(values)

    # Required methods for MutableSet

    def __contains__(self, value: Hashable) -> bool:
        return value in self._d

    def __iter__(self) -> Iterator[T]:
        return iter(self._d)

    def __len__(self) -> int:
        return len(self._d)

    def add(self, value: T) -> None:
        self._d[value] = None

    def discard(self, value: T) -> None:
        del self._d[value]

    # Additional methods

    def update(self, values: Iterable[T]) -> None:
        self._d.update(dict.fromkeys(values))

    def __repr__(self) -> str:
        return f"{type(self).__name__}({list(self)!r})"


class NdimSizeLenMixin: