Dart
dart:collection
Queue<E> abstract class

Queue<E> class

A Queue is a collection that can be manipulated at both ends. One can iterate over the elements of a queue through forEach or with an Iterator.

It is generally not allowed to modify the queue (add or remove entries) while an operation on the queue is being performed, for example during a call to forEach. Modifying the queue while it is being iterated will most likely break the iteration. This goes both for using the iterator directly, or for iterating an Iterable returned by a method like map or where.

Implementers

Constructors

Queue(): Creates a queue.
factory
Queue.from(Iterable elements): Creates a queue containing all elements. [...]
factory
Queue.of(Iterable<E> elements): Creates a queue from elements. [...]
factory

Properties

first → E: Returns the first element. [...]
read-only, inherited
hashCode → int: The hash code for this object. [...]
read-only, inherited
isEmpty → bool: Returns true if there are no elements in this collection. [...]
read-only, inherited
isNotEmpty → bool: Returns true if there is at least one element in this collection. [...]
read-only, inherited
iterator → Iterator<E>: Returns a new Iterator that allows iterating the elements of this Iterable. [...]
read-only, inherited
last → E: Returns the last element. [...]
read-only, inherited
length → int: Returns the number of elements in the iterable. [...]
read-only, inherited
runtimeType → Type: A representation of the runtime type of the object.
read-only, inherited
single → E: Checks that this iterable has only one element, and returns that element. [...]
read-only, inherited

Methods

add(E value) → void: Adds value at the end of the queue.
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.
addFirst(E value) → void: Adds value at the beginning of the queue.
addLast(E value) → void: Adds value at the end of the queue.
cast<R>() → Queue<R>: Provides a view of this queue as a queue of R instances, if necessary. [...]
override
clear() → void: Removes all elements in the queue. The size of the queue becomes zero.
remove(Object value) → bool: Remove a single instance of value from the queue. [...]
removeFirst() → E: Removes and returns the first element of this queue. [...]
removeLast() → E: Removes and returns the last element of the queue. [...]
removeWhere(bool test(E element)) → void: Removes all elements matched by test from the queue. [...]
retainWhere(bool test(E element)) → void: Removes all elements not matched by test from the queue. [...]
any(bool test(E element)) → bool: Checks whether any element of this iterable satisfies test. [...]
inherited
contains(Object element) → bool: Returns true if the collection contains an element equal to element. [...]
inherited
elementAt(int index) → E: Returns the indexth element. [...]
inherited
every(bool test(E element)) → bool: Checks whether every element of this iterable satisfies test. [...]
inherited
expand<T>(Iterable<T> f(E element)) → Iterable<T>: Expands each element of this Iterable into zero or more elements. [...]
inherited
firstWhere(bool test(E element), { E orElse() }) → E: Returns 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>: Returns the lazy concatentation of this iterable and other. [...]
inherited
forEach(void f(E element)) → void: Applies the function f to each element of this collection in iteration order.
inherited
join([String separator = "" ]) → String: Converts each element to a String and concatenates the strings. [...]
inherited
lastWhere(bool test(E element), { E orElse() }) → E: Returns the last element that satisfies the given predicate test. [...]
inherited
map<T>(T f(E e)) → Iterable<T>: Returns a new lazy Iterable with elements that are created by calling f on each element of this Iterable in iteration order. [...]
inherited
noSuchMethod(Invocation invocation) → dynamic: Invoked when a non-existent 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
singleWhere(bool test(E element), { E orElse() }) → E: Returns the single element that satisfies test. [...]
inherited
skip(int count) → Iterable<E>: Returns an Iterable that provides all but the first count elements. [...]
inherited
skipWhile(bool test(E value)) → Iterable<E>: Returns an Iterable that skips leading elements while test is satisfied. [...]
inherited
take(int count) → Iterable<E>: Returns a lazy iterable of the count first elements of this iterable. [...]
inherited
takeWhile(bool test(E value)) → Iterable<E>: Returns 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 this object.
inherited
where(bool test(E element)) → Iterable<E>: Returns a new lazy Iterable with all elements that satisfy the predicate test. [...]
inherited
whereType<T>() → Iterable<T>: Returns a new lazy Iterable with all elements that have type T. [...]
inherited

Operators

operator ==(dynamic other) → bool: The equality operator. [...]
inherited

Static Methods

castFrom<S, T>(Queue<S> source) → Queue<T>: Adapts source to be a Queue<T>. [...]
override