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

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.
difference(Set<Object> other) → Set<E>
Returns a new set with the the elements of this that are not in other. [...]
intersection(Set<Object> other) → Set<E>
Returns a new set which is the intersection between this and other. [...]
lookup(Object element) → E
Throws an UnsupportedError since there's no corresponding method for Maps.
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. [...]
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