description

# DoubleLinkedQueue<E> class final

A Queue implementation based on a double-linked list.

Allows constant time add, remove-at-ends and peek operations.

Inheritance
  - Object
  - Iterable<E>
  - DoubleLinkedQueue
Implemented types
  - Queue<E>
Available extensions
  - EnumByName
  - FutureIterable
  - IterableExtensions
  - IterableToJSIterable
  - NullableIterableExtensions

## Constructors

DoubleLinkedQueue()
DoubleLinkedQueue.from(Iterable elements)
  Creates a double-linked queue containing all `elements`.
  factory
DoubleLinkedQueue.of(Iterable<E> elements)
  Creates a double-linked queue from `elements`.
  factory

## Properties

first → E
  The first element.
  no setteroverride
firstOrNull → T?

  Available on Iterable<T>, provided by the IterableExtensions extension

  The first element of this iterator, or `null` if the iterable is empty.
  no setter
hashCode → int
  The hash code for this object.
  no setterinherited
indexed → Iterable<(int, T)>

  Available on Iterable<T>, provided by the IterableExtensions extension

  Pairs of elements of the indices and elements of this iterable.
  no setter
isEmpty → bool
  Whether this collection has no elements.
  no setteroverride
isNotEmpty → bool
  Whether this collection has at least one element.
  no setterinherited
iterator → _DoubleLinkedQueueIterator<E>
  A new `Iterator` that allows iterating the elements of this `Iterable`.
  no setteroverride
last → E
  The last element.
  no setteroverride
lastOrNull → T?

  Available on Iterable<T>, provided by the IterableExtensions extension

  The last element of this iterable, or `null` if the iterable is empty.
  no setter
length → int
  The number of elements in this Iterable.
  no setteroverride
nonNulls → Iterable<T>

  Available on Iterable<T?>, provided by the NullableIterableExtensions extension

  The non-`null` elements of this iterable.
  no setter
runtimeType → Type
  A representation of the runtime type of the object.
  no setterinherited
single → E
  Checks that this iterable has only one element, and returns that element.
  no setteroverride
singleOrNull → T?

  Available on Iterable<T>, provided by the IterableExtensions extension

  The single element of this iterator, or `null`.
  no setter
toJSIterable → JSIterable<T>

  Available on Iterable<T>, provided by the IterableToJSIterable extension

  A JSIterable wrapper that proxies to the Dart iterable API.
  no setter
wait → Future<List<T>>

  Available on Iterable<Future<T>>, provided by the FutureIterable extension

  Waits for futures in parallel.
  no setter

## Methods

add(E value) → void
  Adds `value` at the end of the queue.
  override
addAll(Iterable<E> iterable) → void
  Adds all elements of `iterable` at the end of the queue. The length of the queue is extended by the length of `iterable`.
  override
addFirst(E value) → void
  Adds `value` at the beginning of the queue.
  override
addLast(E value) → void
  Adds `value` at the end of the queue.
  override
any(bool test(E element)) → bool
  Checks whether any element of this iterable satisfies `test`.
  inherited
asNameMap() → Map<String, T>

  Available on Iterable<T>, provided by the EnumByName extension

  Creates a map from the names of enum values to the values.
byName(String name) → T

  Available on Iterable<T>, provided by the EnumByName extension

  Finds the enum value in this list with name `name`.
cast<R>() → Queue<R>
  A view of this iterable as an iterable of `R` instances.
  override
clear() → void
  Removes all elements in the queue. The size of the queue becomes zero.
  override
contains(Object? element) → bool
  Whether the collection contains an element equal to `element`.
  inherited
elementAt(int index) → E
  Returns the `index`th element.
  inherited
elementAtOrNull(int index) → T?

  Available on Iterable<T>, provided by the IterableExtensions extension

  The element at position `index` of this iterable, or `null`.
every(bool test(E element)) → bool
  Checks whether every element of this iterable satisfies `test`.
  inherited
expand<T>(Iterable<T> toElements(E element)) → Iterable<T>
  Expands each element of this Iterable into zero or more elements.
  inherited
firstEntry() → DoubleLinkedQueueEntry<E>?
  The entry object of the first element in the queue.
firstWhere(bool test(E element), {E orElse()?}) → E
  The first element that satisfies the given predicate `test`.
  inherited
fold<T>(T initialValue, T combine(T previousValue, E element)) → T
  Reduces a collection to a single value by iteratively combining each element of the collection with an existing value
  inherited
followedBy(Iterable<E> other) → Iterable<E>
  Creates the lazy concatenation of this iterable and `other`.
  inherited
forEach(void action(E value)) → void
  Invokes `action` on each element of this iterable in iteration order.
  inherited
forEachEntry(void action(DoubleLinkedQueueEntry<E> element)) → void
  Calls `action` for each entry object of this double-linked queue.
join([String separator = ""]) → String
  Converts each element to a String and concatenates the strings.
  inherited
lastEntry() → DoubleLinkedQueueEntry<E>?
  The entry object of the last element in the queue.
lastWhere(bool test(E element), {E orElse()?}) → E
  The last element that satisfies the given predicate `test`.
  inherited
map<T>(T toElement(E e)) → Iterable<T>
  The current elements of this iterable modified by `toElement`.
  inherited
noSuchMethod(Invocation invocation) → dynamic
  Invoked when a nonexistent method or property is accessed.
  inherited
reduce(E combine(E value, E element)) → E
  Reduces a collection to a single value by iteratively combining elements of the collection using the provided function.
  inherited
remove(Object? o) → bool
  Removes a single instance of `value` from the queue.
  override
removeFirst() → E
  Removes and returns the first element of this queue.
  override
removeLast() → E
  Removes and returns the last element of the queue.
  override
removeWhere(bool test(E element)) → void
  Removes all elements matched by `test` from the queue.
  override
retainWhere(bool test(E element)) → void
  Removes all elements not matched by `test` from the queue.
  override
singleWhere(bool test(E element), {E orElse()?}) → E
  The single element that satisfies `test`.
  inherited
skip(int count) → Iterable<E>
  Creates an Iterable that provides all but the first `count` elements.
  inherited
skipWhile(bool test(E element)) → Iterable<E>
  Creates an `Iterable` that skips leading elements while `test` is satisfied.
  inherited
take(int count) → Iterable<E>
  Creates a lazy iterable of the `count` first elements of this iterable.
  inherited
takeWhile(bool test(E element)) → Iterable<E>
  Creates a lazy iterable of the leading elements satisfying `test`.
  inherited
toList({bool growable = true}) → List<E>
  Creates a List containing the elements of this Iterable.
  inherited
toSet() → Set<E>
  Creates a Set containing the same elements as this iterable.
  inherited
toString() → String
  Returns a string representation of (some of) the elements of `this`.
  override
where(bool test(E element)) → Iterable<E>
  Creates a new lazy Iterable with all elements that satisfy the predicate `test`.
  inherited
whereType<T>() → Iterable<T>
  Creates a new lazy Iterable with all elements that have type `T`.
  inherited

## Operators

operator ==(Object other) → bool
  The equality operator.
  inherited