Base Classes¶

About¶

FrozenBase is the base class for frozendict and FrozenOrderedDict. If you wish to construct your own frozen dictionary classes, you may inherit from this class.

API Reference¶

Base Classes.

Classes:

`DictWrapper`(args, *kwds)	Abstract Mixin class for classes that wrap a dict object or similar.
`FrozenBase`(args, *kwargs)	Abstract Base Class for Frozen dictionaries.
`MutableBase`(args, *kwargs)	Abstract Base Class for mutable dictionaries.

class DictWrapper(*args, **kwds)[source]¶

Bases: Mapping[~KT, ~VT]

Abstract Mixin class for classes that wrap a dict object or similar.

Methods:

`__contains__`(key)	Return `key in self`.
`__eq__`(other)	Return `self == other`.
`__getitem__`(key)	Return `self[key]`.
`__iter__`()	Iterates over the dictionary’s keys.
`__len__`()	Returns the number of keys in the dictionary.
`__repr__`()	Return a string representation of the `DictWrapper`.
`copy`(args, *kwargs)	Return a copy of the dictionary.
`get`(k[, default])	Return the value for `k` if `k` is in the dictionary, else `default`.
`items`()	Returns a set-like object providing a view on the `bdict`'s items.
`keys`()	Returns a set-like object providing a view on the `bdict`'s keys.
`values`()	Returns an object providing a view on the `bdict`'s values.

__contains__(key)[source]¶

Return key in self.

Parameters: key (object)
Return type: bool

__eq__(other)¶

Return self == other.

Return type: bool

__getitem__(key)[source]¶

Return self[key].

Parameters: key (~KT)
Return type: ~VT

__iter__()[source]¶

Iterates over the dictionary’s keys.

Return type: Iterator[~KT]

__len__()[source]¶

Returns the number of keys in the dictionary.

Return type: int

__repr__()[source]¶

Return a string representation of the DictWrapper.

Return type: str

abstract copy(*args, **kwargs)[source]¶

Return a copy of the dictionary.

Return type: ~_D

get(k, default=None)[source]¶

Return the value for k if k is in the dictionary, else default.

Parameters

k – The key to return the value for.
default – The value to return if key is not in the dictionary. Default None.

Overloads

get(k: ~KT) -> Optional[~VT]
get(k: ~KT, default: Union[~VT, ~T] ) -> Union[~VT, ~T]

items()[source]¶

Returns a set-like object providing a view on the bdict's items.

Return type: AbstractSet[Tuple[~KT, ~VT]]

keys()[source]¶

Returns a set-like object providing a view on the bdict's keys.

Return type: AbstractSet[~KT]

values()[source]¶

Returns an object providing a view on the bdict's values.

Return type: ValuesView[~VT]

class FrozenBase(*args, **kwargs)[source]¶

Bases: DictWrapper[~KT, ~VT]

Abstract Base Class for Frozen dictionaries.

Used by frozendict and FrozenOrderedDict.

Custom subclasses must implement at a minimum __init__, copy, fromkeys.

Methods:

`__contains__`(key)	Return `key in self`.
`__eq__`(other)	Return `self == other`.
`__getitem__`(key)	Return `self[key]`.
`__iter__`()	Iterates over the dictionary’s keys.
`__len__`()	Returns the number of keys in the dictionary.
`__repr__`()	Return a string representation of the `DictWrapper`.
`copy`(args, *kwargs)	Return a copy of the dictionary.
`fromkeys`(iterable[, value])	Create a new dictionary with keys from iterable and values set to value.
`get`(k[, default])	Return the value for `k` if `k` is in the dictionary, else `default`.
`items`()	Returns a set-like object providing a view on the `bdict`'s items.
`keys`()	Returns a set-like object providing a view on the `bdict`'s keys.
`values`()	Returns an object providing a view on the `bdict`'s values.

__contains__(key)¶

Return key in self.

Parameters: key (object)
Return type: bool

__eq__(other)¶

Return self == other.

Return type: bool

__getitem__(key)¶

Return self[key].

Parameters: key (~KT)
Return type: ~VT

__iter__()¶

Iterates over the dictionary’s keys.

Return type: Iterator[~KT]

__len__()¶

Returns the number of keys in the dictionary.

Return type: int

__repr__()¶

Return a string representation of the DictWrapper.

Return type: str

abstract copy(*args, **kwargs)¶

Return a copy of the dictionary.

Return type: ~_D

classmethod fromkeys(iterable, value=None)[source]¶

Create a new dictionary with keys from iterable and values set to value.

Return type

FrozenBase[~KT, ~VT]

Overloads

fromkeys(iterable ) -> FrozenBase[KT, Any]
fromkeys(iterable, value ) -> FrozenBase[KT, VT]

get(k, default=None)¶

Return the value for k if k is in the dictionary, else default.

Parameters

k – The key to return the value for.
default – The value to return if key is not in the dictionary. Default None.

items()¶

Returns a set-like object providing a view on the bdict's items.

Return type: AbstractSet[Tuple[~KT, ~VT]]

keys()¶

Returns a set-like object providing a view on the bdict's keys.

Return type: AbstractSet[~KT]

values()¶

Returns an object providing a view on the bdict's values.

Return type: ValuesView[~VT]

class MutableBase(*args, **kwargs)[source]¶

Bases: DictWrapper[~KT, ~VT], MutableMapping[~KT, ~VT]

Abstract Base Class for mutable dictionaries.

Used by NonelessDict and NonelessOrderedDict.

Custom subclasses must implement at a minimum __init__, copy, fromkeys.

Methods:

`__contains__`(key)	Return `key in self`.
`__delitem__`(key)	Delete `self[key]`.
`__eq__`(other)	Return `self == other`.
`__getitem__`(key)	Return `self[key]`.
`__iter__`()	Iterates over the dictionary’s keys.
`__len__`()	Returns the number of keys in the dictionary.
`__repr__`()	Return a string representation of the `DictWrapper`.
`__setitem__`(key, value)	Set `self[key]` to `value`.
`clear`()
`copy`(args, *kwargs)	Return a copy of the dictionary.
`fromkeys`(iterable[, value])	Create a new dictionary with keys from iterable and values set to value.
`get`(k[, default])	Return the value for `k` if `k` is in the dictionary, else `default`.
`items`()	Returns a set-like object providing a view on the `bdict`'s items.
`keys`()	Returns a set-like object providing a view on the `bdict`'s keys.
`pop`(k[,d])	If key is not found, d is returned if given, otherwise KeyError is raised.
`popitem`()	as a 2-tuple; but raise KeyError if D is empty.
`setdefault`(k[,d])
`update`([E, ]**F)	If E present and has a .keys() method, does: for k in E: D[k] = E[k] If E present and lacks .keys() method, does: for (k, v) in E: D[k] = v In either case, this is followed by: for k, v in F.items(): D[k] = v
`values`()	Returns an object providing a view on the `bdict`'s values.

__contains__(key)¶

Return key in self.

Parameters: key (object)
Return type: bool

__delitem__(key)[source]¶: Delete self[key].

__eq__(other)¶

Return self == other.

Return type: bool

__getitem__(key)¶

Return self[key].

Parameters: key (~KT)
Return type: ~VT

__iter__()¶

Iterates over the dictionary’s keys.

Return type: Iterator[~KT]

__len__()¶

Returns the number of keys in the dictionary.

Return type: int

__repr__()¶

Return a string representation of the DictWrapper.

Return type: str

__setitem__(key, value)[source]¶: Set self[key] to value.

clear() → None. Remove all items from D.¶

abstract copy(*args, **kwargs)¶

Return a copy of the dictionary.

Return type: ~_D

classmethod fromkeys(iterable, value=None)[source]¶

Create a new dictionary with keys from iterable and values set to value.

Return type

MutableBase[~KT, ~VT]

Overloads

fromkeys(iterable ) -> MutableBase[KT, Any]
fromkeys(iterable, value ) -> MutableBase[KT, VT]

get(k, default=None)¶

Return the value for k if k is in the dictionary, else default.

Parameters

k – The key to return the value for.
default – The value to return if key is not in the dictionary. Default None.

items()¶

Returns a set-like object providing a view on the bdict's items.

Return type: AbstractSet[Tuple[~KT, ~VT]]

keys()¶

Returns a set-like object providing a view on the bdict's keys.

Return type: AbstractSet[~KT]

pop(k[, d]) → v, remove specified key and return the corresponding value.¶: If key is not found, d is returned if given, otherwise KeyError is raised.

popitem() → (k, v), remove and return some (key, value) pair¶: as a 2-tuple; but raise KeyError if D is empty.

setdefault(k[, d]) → D.get(k,d), also set D[k]=d if k not in D¶

update([E, ]**F) → None. Update D from mapping/iterable E and F.¶: If E present and has a .keys() method, does: for k in E: D[k] = E[k] If E present and lacks .keys() method, does: for (k, v) in E: D[k] = v In either case, this is followed by: for k, v in F.items(): D[k] = v

values()¶

Returns an object providing a view on the bdict's values.

Return type: ValuesView[~VT]