MapKeySet<E> class

An unmodifiable Set view of the keys of a Map.

The set delegates all operations to the underlying map.

A Map can only contain each key once, so its keys can always be viewed as a Set without any loss, even if the Map.keys getter only shows an Iterable view of the keys.

Note that lookup is not supported for this set.

Mixed in types

UnmodifiableSetMixin<E>

Constructors

MapKeySet(Map<E, dynamic> base)

Properties

isEmpty → bool: Returns true if there are no elements in this collection. [...]
read-only
isNotEmpty → bool: Returns true if there is at least one element in this collection. [...]
read-only
length → int: Returns the number of elements in this. [...]
read-only
first → E: Returns the first element. [...]
read-only, inherited
hashCode → int: The hash code for this object. [...]
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
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

cast<T>() → Set<T>: Provides a view of this iterable as an iterable of R instances. [...]
contains(Object element) → bool: Returns true if the collection contains an element equal to element. [...]
containsAll(Iterable<Object> other) → bool: Returns whether this Set contains all the elements of other.
override
difference(Set<Object> other) → Set<E>: Returns a new set with the the elements of this that are not in other. [...]
override
intersection(Set<Object> other) → Set<E>: Returns a new set which is the intersection between this and other. [...]
override
lookup(Object element) → E: Throws an UnsupportedError since there's no corresponding method for Maps.
override
retype<T>() → Set<T>
toString() → String: Returns a string representation of this object.
union(Set<E> other) → Set<E>: Returns a new set which contains all the elements of this and other. [...]
override
add(E value) → bool: Throws an UnsupportedError; operations that change the set are disallowed.
inherited
addAll(Iterable<E> elements) → void: Throws an UnsupportedError; operations that change the set are disallowed.
inherited
any(bool test(E element)) → bool: Checks whether any element of this iterable satisfies test. [...]
inherited
clear() → void: Throws an UnsupportedError; operations that change the set are disallowed.
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 element)) → 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
remove(Object value) → bool: Throws an UnsupportedError; operations that change the set are disallowed.
inherited
removeAll(Iterable elements) → void: Throws an UnsupportedError; operations that change the set are disallowed.
inherited
removeWhere(bool test(E element)) → void: Throws an UnsupportedError; operations that change the set are disallowed.
inherited
retainAll(Iterable elements) → void: Throws an UnsupportedError; operations that change the set are disallowed.
inherited
retainWhere(bool test(E element)) → void: Throws an UnsupportedError; operations that change the set are disallowed.
inherited
singleWhere(bool test(E element), { E orElse() }) → E: Returns the single element that satisfies test. [...]
inherited
skip(int n) → 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 n) → 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
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

collection library

MapKeySet<E> class

Constructors

Properties

Methods

Operators