Skip to content

collections

A ChainMap groups multiple dictionaries together to create a single, updateable view. Like Python's collections.ChainMap.

import collections

ChainMap

A ChainMap groups multiple dictionaries together to create a single, updateable view. Like Python's collections.ChainMap.

Properties

Name Type Description
maps System.Collections.Generic.List[dict[K, V]] The list of underlying mappings.

new_child(m: dict[K, V]? = null) -> ChainMap[K, V]

Return a new ChainMap with a new map followed by all previous maps. If no map is provided, an empty dict is used.

get(key: K, @default: V = default!) -> V

Get a value, searching through all maps.

keys() -> Iterable[K]

Return all unique keys across all maps.

pop(key: K) -> V

Remove key from the first mapping. Raises KeyError if not found in first mapping.

clear()

Clear the first mapping.

Deque

A deque (double-ended queue) is a generalization of stacks and queues that supports adding and removing elements from either end.

Properties

Name Type Description
count int Gets the number of elements in the deque.

append(x: T)

Add x to the right side of the deque.

appendleft(x: T)

Add x to the left side of the deque.

pop() -> T

Remove and return an element from the right side of the deque. If no elements are present, raises an IndexError.

popleft() -> T

Remove and return an element from the left side of the deque. If no elements are present, raises an IndexError.

clear()

Remove all elements from the deque.

extend(iterable: Iterable[T])

Extend the right side of the deque by appending elements from the iterable.

extendleft(iterable: Iterable[T])

Extend the left side of the deque by appending elements from the iterable.

Counter

A deque (double-ended queue) is a generalization of stacks and queues that supports adding and removing elements from either end.

Properties

Name Type Description
keys Iterable[T] The keys of the counter.

elements() -> Iterable[T]

Elements are returned in arbitrary order. Each element is repeated count times.

update(iterable: Iterable[T])

Update counts from an iterable or another mapping.

subtract(iterable: Iterable[T])

Subtract counts. Elements are subtracted from an iterable. Counts can go below zero.

subtract(other: Counter[T])

Subtract counts from another Counter. Counts can go below zero.

copy() -> Counter[T]

Return a shallow copy of this counter.

total() -> int

Return the sum of all counts.

clear()

Remove all elements from the counter.

DefaultDict

A deque (double-ended queue) is a generalization of stacks and queues that supports adding and removing elements from either end.

Properties

Name Type Description
keys Iterable[TKey] The keys of the dictionary.
values Iterable[TValue] The values of the dictionary.
default_factory Func[TValue] The default factory function used for missing keys.
count int The number of items in the defaultdict.

get(key: TKey, default_value: TValue = default!) -> TValue

Get the value for a key, or return a default value if the key is not present.

copy() -> DefaultDict[TKey, TValue]

Return a shallow copy of this defaultdict, preserving the default factory.

clear()

Remove all items from the defaultdict.

pop(key: TKey) -> TValue

Remove the specified key and return its value. Raises KeyError if the key is not found.

pop(key: TKey, default_value: TValue) -> TValue

Remove the specified key and return its value. If the key is not found, return defaultValue.

update(other: IDictionary[TKey, TValue])

Update the defaultdict with key-value pairs from another dictionary.

update(t_value: IEnumerable<(TKey,)

Update the defaultdict with key-value pairs from an iterable of tuples.

set_default(key: TKey, default_value: TValue) -> TValue

If key is in the dictionary, return its value. If not, insert key with defaultValue and return defaultValue.

remove(key: TKey)

Removes the item with the specified key from the defaultdict.

Raises:

  • KeyError -- Thrown if the key does not exist.

to_dictionary() -> Dictionary[TKey, TValue]

Convert to a standard .NET Dictionary.

OrderedDict

A dictionary that remembers the order in which items were inserted. Like Python's collections.OrderedDict.

Properties

Name Type Description
count int Gets the number of key/value pairs.

pop(key: K) -> V

Remove the specified key and return its value.

pop(key: K, @default: V) -> V

Remove the specified key and return its value, or return default if not found.

move_to_end(key: K, last: bool = true)

Move an existing key to either end of an ordered dictionary. If last is true, move to the end; if false, move to the beginning.

clear()

Remove all items from the dictionary.

keys() -> Iterable[K]

Return the keys in insertion order.

values() -> Iterable[V]

Return the values in insertion order.

copy() -> OrderedDict[K, V]

Return a shallow copy.

get(key: K, @default: V = default!) -> V

Get the value for a key, or a default.