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NestedDict

Bases: MutableMapping

Nested dictionary data structure.

Handle nested dictionaries with an interface similar to standard dictionaries.

Parameters:

Name Type Description Default
dictionary dict

Input nested dictionary.

 None
copy bool

Set to True to copy the input dictionary.

 False
See Also

NestedDict.from_product: Initialize from cartesian product.

NestedDict.from_tuples: Initialize from list of tuples.

Examples:

Initialize from a nested dictionary.

>>> d = {"a": {"a": 0, "b": 1}, "b": 2}
>>> nd = NestedDict(d)
>>> nd
NestedDict({'a': {'a': 0, 'b': 1}, 'b': 2})

Get an item.

>>> nd["a"]
{'a': 0, 'b': 1}
>>> nd[("a", "b")]
1

Set an item.

>>> nd[("c", "a")] = 3
>>> nd
NestedDict({'a': {'a': 0, 'b': 1}, 'b': 2, 'c': {'a': 3}})

Delete an item.

>>> del nd["c"]
>>> nd
NestedDict({'a': {'a': 0, 'b': 1}, 'b': 2})

Iterate over keys.

>>> [key for key in nd]
[('a', 'a'), ('a', 'b'), ('b',)]
>>> [key for key in nd.keys()]
[('a', 'a'), ('a', 'b'), ('b',)]

Iterate over values.

>>> [value for value in nd.values()]
[0, 1, 2]

Iterate over items.

>>> [item for item in nd.items()]
[(('a', 'a'), 0), (('a', 'b'), 1), (('b',), 2)]
Source code in ndicts\nested_dict.py 
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class NestedDict(MutableMapping):
    """
    Nested dictionary data structure.

    Handle nested dictionaries with an interface
    similar to standard dictionaries.

    Args:
        dictionary (dict): Input nested dictionary.
        copy (bool): Set to True to copy the input dictionary.

    See Also:
        NestedDict.from_product: Initialize from cartesian product.

        NestedDict.from_tuples: Initialize from list of tuples.

    Examples:
        Initialize from a nested dictionary.

        >>> d = {"a": {"a": 0, "b": 1}, "b": 2}
        >>> nd = NestedDict(d)
        >>> nd
        NestedDict({'a': {'a': 0, 'b': 1}, 'b': 2})

        Get an item.

        >>> nd["a"]
        {'a': 0, 'b': 1}
        >>> nd[("a", "b")]
        1

        Set an item.

        >>> nd[("c", "a")] = 3
        >>> nd
        NestedDict({'a': {'a': 0, 'b': 1}, 'b': 2, 'c': {'a': 3}})

        Delete an item.

        >>> del nd["c"]
        >>> nd
        NestedDict({'a': {'a': 0, 'b': 1}, 'b': 2})

        Iterate over keys.

        >>> [key for key in nd]
        [('a', 'a'), ('a', 'b'), ('b',)]
        >>> [key for key in nd.keys()]
        [('a', 'a'), ('a', 'b'), ('b',)]

        Iterate over values.

        >>> [value for value in nd.values()]
        [0, 1, 2]

        Iterate over items.

        >>> [item for item in nd.items()]
        [(('a', 'a'), 0), (('a', 'b'), 1), (('b',), 2)]
    """

    @classmethod
    def from_tuples(cls, tuples: List[Iterable], values: Union[Any, Iterable] = None) -> T:
        """
        Initialize a NestedDict from a list of iterables.

        Args:
            tuples:
                Tuples corresponding to the keys of the NestedDict.
            values:
                If values is an iterable but not a string,
                its values will become to those of the NestedDict.
                If a non-iterable or string is passed,
                it will be assigned to each value of the NestedDict.

        Returns:
            NestedDict

        Raises:
            UnequalIterablesError: If the keys and values have different length.

        Examples:
            >>> tuples = [("a", "aa"), ("b",)]
            >>> NestedDict.from_tuples(tuples)
            NestedDict({'a': {'aa': None}, 'b': None})

            Initialize with a single value.

            >>> NestedDict.from_tuples(tuples, values=0)
            NestedDict({'a': {'aa': 0}, 'b': 0})

            Initialize with different values.

            >>> NestedDict.from_tuples(tuples, values=[0, 1])
            NestedDict({'a': {'aa': 0}, 'b': 1})

            Passing values with the wrong size will throw an exception.

            >>> NestedDict.from_tuples(tuples, values=range(99))
            Traceback (most recent call last):
            ...
            more_itertools.recipes.UnequalIterablesError: Iterables have different lengths...
        """
        nd = cls()
        if isinstance(values, Iterable) and not isinstance(values, str):
            for key, value in zip_equal(tuples, values):
                nd[key] = value
        else:
            for key in tuples:
                nd[key] = values
        return nd

    @classmethod
    def from_product(cls, iterables: List[Iterable], values: Union[Any, Iterable] = None) -> T:
        """
        Initialize a NestedDict by cartesian product.

        Args:
            iterables:
                Input iterables.
            values:
                If values is an iterable but not a string,
                it will be assigned to the values of the NestedDict.
                If a non-iterable or string is passed,
                it will be assigned to each value of the NestedDict.

        Returns:
            NestedDict

        Raises:
            UnequalIterablesError: If the keys and values have different length.

        Examples:
            >>> iterables = [("A", "B"), ("a", "b")]
            >>> NestedDict.from_product(iterables)
            NestedDict({'A': {'a': None, 'b': None}, 'B': {'a': None, 'b': None}})

            Initialize with a single value.

            >>> NestedDict.from_product(iterables, values=0)
            NestedDict({'A': {'a': 0, 'b': 0}, 'B': {'a': 0, 'b': 0}})

            Initialize with different values.

            >>> NestedDict.from_product(iterables, values=[0, 1, 2, 3])
            NestedDict({'A': {'a': 0, 'b': 1}, 'B': {'a': 2, 'b': 3}})

            Passing values with the wrong size will throw an exception.

            >>> NestedDict.from_product(iterables, values=range(99))
            Traceback (most recent call last):
            ...
            more_itertools.recipes.UnequalIterablesError: Iterables have different lengths
        """
        keys = product(*iterables)
        return cls.from_tuples(keys, values)

    def __init__(self, dictionary: dict = None, copy: bool = False) -> None:
        """
        Initialize a NestedDict from a dictionary.

        See class docstring.
        """
        if dictionary is None:
            dictionary = {}
        self._ndict = deepcopy(dictionary) if copy else dictionary

    def __getitem__(self, key: Union[Any, Tuple]) -> Any:
        """
        Get item associated to the key.

        Args:
            key:
                Either comma-separated values or tuples.

        Returns:
            Value associated to the key.

        Raises:
            KeyError: If the key does not belong to the NestedDict.

        Examples:
            >>> d = {"a": {"a": 0, "b": 1}}
            >>> nd = NestedDict(d)

            Get the first level.

            >>> nd["a"]
            {'a': 0, 'b': 1}

            Get a deeper value.

            >>> nd["a", "a"]
            0

            Tuples can be passed too.
            >>> nd[("a", "b")]
            1

            An exception is thrown if they key does not exist.

            >>> nd["z"]
            Traceback (most recent call last):
            ...
            KeyError: ('z',)
        """
        if not isinstance(key, tuple):
            key = (key,)
        item = self._ndict

        for k in key:
            try:
                item = item[k]
            except KeyError:
                raise KeyError(key)
            except TypeError:
                raise KeyError(key)
        return item

    def __setitem__(self, key: Union[Any, Tuple], value: Any) -> None:
        """
        Set the key to the given value.

        If the key does not exist it is created.

        Args:
            key: Key to be set.
            value: New value for the key.

        Examples:
            Set an existing key.

            >>> nd = NestedDict({"a": {"aa": 0}})
            >>> nd["a", "aa"] = 1
            >>> nd
            NestedDict({'a': {'aa': 1}})

            Set a new key.
            >>> nd["a", "ab"] = 2
            >>> nd
            NestedDict({'a': {'aa': 1, 'ab': 2}})
        """
        if not isinstance(key, tuple):
            key = (key,)
        item = self._ndict
        for k in key[:-1]:
            item = item.setdefault(k, {})
        item[key[-1]] = value

    def __delitem__(self, key: Union[Any, Tuple]) -> None:
        """
        Delete item corresponding to the key.

        If the levels above are left empty, they are deleted.

        Args:
            key: Key as defined in NestedDict.__getitem__

        Examples:
            >>> d = {"a": {"aa": {"aaa": 0}}, "b": 1}
            >>> nd = NestedDict(d)
            >>> del nd["b"]
            >>> nd
            NestedDict({'a': {'aa': {'aaa': 0}}})

            Levels which are left empty after deleting an item are deleted too.

            >>> del nd["a", "aa", "aaa"]
            >>> nd
            NestedDict({})
        """
        if not isinstance(key, tuple):
            key = (key,)
        new_key, last_key = key[:-1], key[-1]
        del self[new_key][last_key]

        if (new_key != ()) & (self[new_key] == {}):
            self.__delitem__(new_key)

    def __iter__(self) -> Generator:
        """
        Iterate over a NestedDict.

        Yield only the keys that are associated to a leaf value.

        Note:
            NestedDict is a MutableMapping, thus it is possible
            to iterate over values, keys and items exactly as a dictionary.
            See the examples.

        Examples:
            >>> d = {"a": {"aa": 0, "ab": 1}, "b": 2}
            >>> nd = NestedDict(d)
            >>> [key for key in nd]
            [('a', 'aa'), ('a', 'ab'), ('b',)]

            Alternative to iterate over the keys.

            >>> [key for key in nd.keys()]
            [('a', 'aa'), ('a', 'ab'), ('b',)]

            Iterate over the leaf values.

            >>> [value for value in nd.values()]
            [0, 1, 2]

            Iterate over the items.
            >>> [item for item in nd.items()]
            [(('a', 'aa'), 0), (('a', 'ab'), 1), (('b',), 2)]
        """
        def wrapped(ndict, key=[]):
            """Traverse the nested dictionary recursively,
            yield the key once a leaf value is reached."""
            if not isinstance(ndict, dict):
                yield tuple(key)
            else:
                for node, branch in ndict.items():
                    key.append(node)
                    yield from wrapped(branch, key)
                    key.pop()

        return wrapped(self._ndict)

    def __len__(self) -> int:
        """
        Number of leaf values.

        Examples:
            >>> nd = NestedDict({"a": {"aa": 0, "ab": 0}, "b": 0})
            >>> len(nd)
            3
        """
        length = 0
        for _ in self:
            length += 1
        return length

    def __repr__(self) -> str:
        return f"{self.__class__.__qualname__}({self._ndict})"

    @property
    def extract(self):
        """
        Get item as a NestedDict.

        Instead of a dict or a value, a NestedDict is returned.
        The method can be used for filtering.
        An empty string "" can be used as a wildcard to match all levels.

        Examples:
             >>> nd = NestedDict.from_product(["ab", "xy"], values=0)
             >>> nd
             NestedDict({'a': {'x': 0, 'y': 0}, 'b': {'x': 0, 'y': 0}})
             >>> nd.extract["a"]
             NestedDict({'a': {'x': 0, 'y': 0}})

             Use the wildcard to extract all items with "x" on the second level.
             >>> nd.extract["", "x"]
             NestedDict({'a': {'x': 0}, 'b': {'x': 0}})
        """
        return _Extractor(self)

    def rows(self) -> Generator:
        """
        Yield the NestedDict row by row.

        A row is obtained by adding the leaf value
        to the sequence of its key.

        Notes:
            This method can be useful to export
            a NestedDict to a pandas DataFrame.

        Yields:
            A row of the NestedDict.

        Examples:
            >>> nd = NestedDict({"a": 0, "b": {"ba": 1}, "c": 2})
            >>> [row for row in nd.rows()]
            [('a', 0), ('b', 'ba', 1), ('c', 2)]
        """
        return ((*key, value) for key, value in self.items())

    def copy(self) -> T:
        """Return a deep copy."""
        return deepcopy(self)

    def to_dict(self) -> dict:
        """Return a copy as a dictionary."""
        return deepcopy(self._ndict)

extract property

Get item as a NestedDict.

Instead of a dict or a value, a NestedDict is returned. The method can be used for filtering. An empty string "" can be used as a wildcard to match all levels.

Examples:

>>> nd = NestedDict.from_product(["ab", "xy"], values=0)
>>> nd
NestedDict({'a': {'x': 0, 'y': 0}, 'b': {'x': 0, 'y': 0}})
>>> nd.extract["a"]
NestedDict({'a': {'x': 0, 'y': 0}})

Use the wildcard to extract all items with "x" on the second level.

>>> nd.extract["", "x"]
NestedDict({'a': {'x': 0}, 'b': {'x': 0}})

__delitem__(key)

Delete item corresponding to the key.

If the levels above are left empty, they are deleted.

Parameters:

Name Type Description Default
key Union[Any, Tuple]

Key as defined in NestedDict.getitem

 required

Examples:

>>> d = {"a": {"aa": {"aaa": 0}}, "b": 1}
>>> nd = NestedDict(d)
>>> del nd["b"]
>>> nd
NestedDict({'a': {'aa': {'aaa': 0}}})

Levels which are left empty after deleting an item are deleted too.

>>> del nd["a", "aa", "aaa"]
>>> nd
NestedDict({})
Source code in ndicts\nested_dict.py 
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def __delitem__(self, key: Union[Any, Tuple]) -> None:
    """
    Delete item corresponding to the key.

    If the levels above are left empty, they are deleted.

    Args:
        key: Key as defined in NestedDict.__getitem__

    Examples:
        >>> d = {"a": {"aa": {"aaa": 0}}, "b": 1}
        >>> nd = NestedDict(d)
        >>> del nd["b"]
        >>> nd
        NestedDict({'a': {'aa': {'aaa': 0}}})

        Levels which are left empty after deleting an item are deleted too.

        >>> del nd["a", "aa", "aaa"]
        >>> nd
        NestedDict({})
    """
    if not isinstance(key, tuple):
        key = (key,)
    new_key, last_key = key[:-1], key[-1]
    del self[new_key][last_key]

    if (new_key != ()) & (self[new_key] == {}):
        self.__delitem__(new_key)

__getitem__(key)

Get item associated to the key.

Parameters:

Name Type Description Default
key Union[Any, Tuple]

Either comma-separated values or tuples.

 required

Returns:

Type Description
Any

Value associated to the key.

Raises:

Type Description
KeyError

If the key does not belong to the NestedDict.

Examples:

>>> d = {"a": {"a": 0, "b": 1}}
>>> nd = NestedDict(d)

Get the first level.

>>> nd["a"]
{'a': 0, 'b': 1}

Get a deeper value.

>>> nd["a", "a"]
0

Tuples can be passed too.

>>> nd[("a", "b")]
1

An exception is thrown if they key does not exist.

>>> nd["z"]
Traceback (most recent call last):
...
KeyError: ('z',)
Source code in ndicts\nested_dict.py 
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def __getitem__(self, key: Union[Any, Tuple]) -> Any:
    """
    Get item associated to the key.

    Args:
        key:
            Either comma-separated values or tuples.

    Returns:
        Value associated to the key.

    Raises:
        KeyError: If the key does not belong to the NestedDict.

    Examples:
        >>> d = {"a": {"a": 0, "b": 1}}
        >>> nd = NestedDict(d)

        Get the first level.

        >>> nd["a"]
        {'a': 0, 'b': 1}

        Get a deeper value.

        >>> nd["a", "a"]
        0

        Tuples can be passed too.
        >>> nd[("a", "b")]
        1

        An exception is thrown if they key does not exist.

        >>> nd["z"]
        Traceback (most recent call last):
        ...
        KeyError: ('z',)
    """
    if not isinstance(key, tuple):
        key = (key,)
    item = self._ndict

    for k in key:
        try:
            item = item[k]
        except KeyError:
            raise KeyError(key)
        except TypeError:
            raise KeyError(key)
    return item

__init__(dictionary=None, copy=False)

Initialize a NestedDict from a dictionary.

See class docstring.

Source code in ndicts\nested_dict.py 
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def __init__(self, dictionary: dict = None, copy: bool = False) -> None:
    """
    Initialize a NestedDict from a dictionary.

    See class docstring.
    """
    if dictionary is None:
        dictionary = {}
    self._ndict = deepcopy(dictionary) if copy else dictionary

__iter__()

Iterate over a NestedDict.

Yield only the keys that are associated to a leaf value.

Note

NestedDict is a MutableMapping, thus it is possible to iterate over values, keys and items exactly as a dictionary. See the examples.

Examples:

>>> d = {"a": {"aa": 0, "ab": 1}, "b": 2}
>>> nd = NestedDict(d)
>>> [key for key in nd]
[('a', 'aa'), ('a', 'ab'), ('b',)]

Alternative to iterate over the keys.

>>> [key for key in nd.keys()]
[('a', 'aa'), ('a', 'ab'), ('b',)]

Iterate over the leaf values.

>>> [value for value in nd.values()]
[0, 1, 2]

Iterate over the items.

>>> [item for item in nd.items()]
[(('a', 'aa'), 0), (('a', 'ab'), 1), (('b',), 2)]
Source code in ndicts\nested_dict.py 
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def __iter__(self) -> Generator:
    """
    Iterate over a NestedDict.

    Yield only the keys that are associated to a leaf value.

    Note:
        NestedDict is a MutableMapping, thus it is possible
        to iterate over values, keys and items exactly as a dictionary.
        See the examples.

    Examples:
        >>> d = {"a": {"aa": 0, "ab": 1}, "b": 2}
        >>> nd = NestedDict(d)
        >>> [key for key in nd]
        [('a', 'aa'), ('a', 'ab'), ('b',)]

        Alternative to iterate over the keys.

        >>> [key for key in nd.keys()]
        [('a', 'aa'), ('a', 'ab'), ('b',)]

        Iterate over the leaf values.

        >>> [value for value in nd.values()]
        [0, 1, 2]

        Iterate over the items.
        >>> [item for item in nd.items()]
        [(('a', 'aa'), 0), (('a', 'ab'), 1), (('b',), 2)]
    """
    def wrapped(ndict, key=[]):
        """Traverse the nested dictionary recursively,
        yield the key once a leaf value is reached."""
        if not isinstance(ndict, dict):
            yield tuple(key)
        else:
            for node, branch in ndict.items():
                key.append(node)
                yield from wrapped(branch, key)
                key.pop()

    return wrapped(self._ndict)

__len__()

Number of leaf values.

Examples:

>>> nd = NestedDict({"a": {"aa": 0, "ab": 0}, "b": 0})
>>> len(nd)
3
Source code in ndicts\nested_dict.py 
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def __len__(self) -> int:
    """
    Number of leaf values.

    Examples:
        >>> nd = NestedDict({"a": {"aa": 0, "ab": 0}, "b": 0})
        >>> len(nd)
        3
    """
    length = 0
    for _ in self:
        length += 1
    return length

__setitem__(key, value)

Set the key to the given value.

If the key does not exist it is created.

Parameters:

Name Type Description Default
key Union[Any, Tuple]

Key to be set.

 required
value Any

New value for the key.

 required

Examples:

Set an existing key.

>>> nd = NestedDict({"a": {"aa": 0}})
>>> nd["a", "aa"] = 1
>>> nd
NestedDict({'a': {'aa': 1}})

Set a new key.

>>> nd["a", "ab"] = 2
>>> nd
NestedDict({'a': {'aa': 1, 'ab': 2}})
Source code in ndicts\nested_dict.py 
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def __setitem__(self, key: Union[Any, Tuple], value: Any) -> None:
    """
    Set the key to the given value.

    If the key does not exist it is created.

    Args:
        key: Key to be set.
        value: New value for the key.

    Examples:
        Set an existing key.

        >>> nd = NestedDict({"a": {"aa": 0}})
        >>> nd["a", "aa"] = 1
        >>> nd
        NestedDict({'a': {'aa': 1}})

        Set a new key.
        >>> nd["a", "ab"] = 2
        >>> nd
        NestedDict({'a': {'aa': 1, 'ab': 2}})
    """
    if not isinstance(key, tuple):
        key = (key,)
    item = self._ndict
    for k in key[:-1]:
        item = item.setdefault(k, {})
    item[key[-1]] = value

copy()

Return a deep copy.

Source code in ndicts\nested_dict.py 
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def copy(self) -> T:
    """Return a deep copy."""
    return deepcopy(self)

from_product(iterables, values=None) classmethod

Initialize a NestedDict by cartesian product.

Parameters:

Name Type Description Default
iterables List[Iterable]

Input iterables.

 required
values Union[Any, Iterable]

If values is an iterable but not a string, it will be assigned to the values of the NestedDict. If a non-iterable or string is passed, it will be assigned to each value of the NestedDict.

 None

Returns:

Type Description
T

NestedDict

Raises:

Type Description
UnequalIterablesError

If the keys and values have different length.

Examples:

>>> iterables = [("A", "B"), ("a", "b")]
>>> NestedDict.from_product(iterables)
NestedDict({'A': {'a': None, 'b': None}, 'B': {'a': None, 'b': None}})

Initialize with a single value.

>>> NestedDict.from_product(iterables, values=0)
NestedDict({'A': {'a': 0, 'b': 0}, 'B': {'a': 0, 'b': 0}})

Initialize with different values.

>>> NestedDict.from_product(iterables, values=[0, 1, 2, 3])
NestedDict({'A': {'a': 0, 'b': 1}, 'B': {'a': 2, 'b': 3}})

Passing values with the wrong size will throw an exception.

>>> NestedDict.from_product(iterables, values=range(99))
Traceback (most recent call last):
...
more_itertools.recipes.UnequalIterablesError: Iterables have different lengths
Source code in ndicts\nested_dict.py 
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@classmethod
def from_product(cls, iterables: List[Iterable], values: Union[Any, Iterable] = None) -> T:
    """
    Initialize a NestedDict by cartesian product.

    Args:
        iterables:
            Input iterables.
        values:
            If values is an iterable but not a string,
            it will be assigned to the values of the NestedDict.
            If a non-iterable or string is passed,
            it will be assigned to each value of the NestedDict.

    Returns:
        NestedDict

    Raises:
        UnequalIterablesError: If the keys and values have different length.

    Examples:
        >>> iterables = [("A", "B"), ("a", "b")]
        >>> NestedDict.from_product(iterables)
        NestedDict({'A': {'a': None, 'b': None}, 'B': {'a': None, 'b': None}})

        Initialize with a single value.

        >>> NestedDict.from_product(iterables, values=0)
        NestedDict({'A': {'a': 0, 'b': 0}, 'B': {'a': 0, 'b': 0}})

        Initialize with different values.

        >>> NestedDict.from_product(iterables, values=[0, 1, 2, 3])
        NestedDict({'A': {'a': 0, 'b': 1}, 'B': {'a': 2, 'b': 3}})

        Passing values with the wrong size will throw an exception.

        >>> NestedDict.from_product(iterables, values=range(99))
        Traceback (most recent call last):
        ...
        more_itertools.recipes.UnequalIterablesError: Iterables have different lengths
    """
    keys = product(*iterables)
    return cls.from_tuples(keys, values)

from_tuples(tuples, values=None) classmethod

Initialize a NestedDict from a list of iterables.

Parameters:

Name Type Description Default
tuples List[Iterable]

Tuples corresponding to the keys of the NestedDict.

 required
values Union[Any, Iterable]

If values is an iterable but not a string, its values will become to those of the NestedDict. If a non-iterable or string is passed, it will be assigned to each value of the NestedDict.

 None

Returns:

Type Description
T

NestedDict

Raises:

Type Description
UnequalIterablesError

If the keys and values have different length.

Examples:

>>> tuples = [("a", "aa"), ("b",)]
>>> NestedDict.from_tuples(tuples)
NestedDict({'a': {'aa': None}, 'b': None})

Initialize with a single value.

>>> NestedDict.from_tuples(tuples, values=0)
NestedDict({'a': {'aa': 0}, 'b': 0})

Initialize with different values.

>>> NestedDict.from_tuples(tuples, values=[0, 1])
NestedDict({'a': {'aa': 0}, 'b': 1})

Passing values with the wrong size will throw an exception.

>>> NestedDict.from_tuples(tuples, values=range(99))
Traceback (most recent call last):
...
more_itertools.recipes.UnequalIterablesError: Iterables have different lengths...
Source code in ndicts\nested_dict.py 
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@classmethod
def from_tuples(cls, tuples: List[Iterable], values: Union[Any, Iterable] = None) -> T:
    """
    Initialize a NestedDict from a list of iterables.

    Args:
        tuples:
            Tuples corresponding to the keys of the NestedDict.
        values:
            If values is an iterable but not a string,
            its values will become to those of the NestedDict.
            If a non-iterable or string is passed,
            it will be assigned to each value of the NestedDict.

    Returns:
        NestedDict

    Raises:
        UnequalIterablesError: If the keys and values have different length.

    Examples:
        >>> tuples = [("a", "aa"), ("b",)]
        >>> NestedDict.from_tuples(tuples)
        NestedDict({'a': {'aa': None}, 'b': None})

        Initialize with a single value.

        >>> NestedDict.from_tuples(tuples, values=0)
        NestedDict({'a': {'aa': 0}, 'b': 0})

        Initialize with different values.

        >>> NestedDict.from_tuples(tuples, values=[0, 1])
        NestedDict({'a': {'aa': 0}, 'b': 1})

        Passing values with the wrong size will throw an exception.

        >>> NestedDict.from_tuples(tuples, values=range(99))
        Traceback (most recent call last):
        ...
        more_itertools.recipes.UnequalIterablesError: Iterables have different lengths...
    """
    nd = cls()
    if isinstance(values, Iterable) and not isinstance(values, str):
        for key, value in zip_equal(tuples, values):
            nd[key] = value
    else:
        for key in tuples:
            nd[key] = values
    return nd

rows()

Yield the NestedDict row by row.

A row is obtained by adding the leaf value to the sequence of its key.

Notes

This method can be useful to export a NestedDict to a pandas DataFrame.

Yields:

Type Description
Generator

A row of the NestedDict.

Examples:

>>> nd = NestedDict({"a": 0, "b": {"ba": 1}, "c": 2})
>>> [row for row in nd.rows()]
[('a', 0), ('b', 'ba', 1), ('c', 2)]
Source code in ndicts\nested_dict.py 
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def rows(self) -> Generator:
    """
    Yield the NestedDict row by row.

    A row is obtained by adding the leaf value
    to the sequence of its key.

    Notes:
        This method can be useful to export
        a NestedDict to a pandas DataFrame.

    Yields:
        A row of the NestedDict.

    Examples:
        >>> nd = NestedDict({"a": 0, "b": {"ba": 1}, "c": 2})
        >>> [row for row in nd.rows()]
        [('a', 0), ('b', 'ba', 1), ('c', 2)]
    """
    return ((*key, value) for key, value in self.items())

to_dict()

Return a copy as a dictionary.

Source code in ndicts\nested_dict.py 
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def to_dict(self) -> dict:
    """Return a copy as a dictionary."""
    return deepcopy(self._ndict)