SetSignal<E> class

A reactive Signal that holds a Set and implements the Set interface.

SetSignal lets you listen to changes on a set reactively and mutate it directly using standard set operations (like add, addAll, remove, clear, etc.). Any mutations automatically trigger reactive updates to all active listeners (e.g., inside an effect or computed).

Additionally, SetSignal defines convenient operators:

<< injects/adds all items from another set into the current set.
& forks/unions the set with another set into a new SetSignal.
| pipes/unions the set with another signal holding an iterable into a new SetSignal.

Example Usage

import 'package:signals/signals.dart';

void main() {
  final numbers = setSignal<int>({1, 2, 3});

  effect(() {
    print('Set content: $numbers, Length: ${numbers.length}');
  }); // Prints: "Set content: {1, 2, 3}, Length: 3"

  // Standard mutation (triggers updates)
  numbers.add(4); // Prints: "Set content: {1, 2, 3, 4}, Length: 4"

  // Removing an element (triggers updates)
  numbers.remove(1); // Prints: "Set content: {2, 3, 4}, Length: 3"

  // Set intersection (reactive query)
  final common = numbers.intersection({3, 4, 5});
  print(common); // Prints: {3, 4}
}

:::tip Mutating the collection directly calls the reactive set() routine under the hood automatically. You do not need to assign numbers.value = ... manually! :::

Inheritance

Object
Signal<Set<E>>
SetSignal

Implemented types

Set<E>

Mixed-in types

IterableSignalMixin<E, Set<E>>
SetSignalMixin<E, Set<E>>

Available extensions

Constructors

SetSignal(Set<E> value, {SetSignalOptions<E>? options, @Deprecated('Use options: SetSignalOptions(autoDispose: ...) instead') bool? autoDispose, @Deprecated('Use options: SetSignalOptions(name: ...) instead') String? debugLabel}): Creates a SetSignal with the given value.

Properties

$ → Signal<Iterable<E>>: Available on Iterable<E>, provided by the SignalIterableExtensions extension
Return a signal from a Iterable value
no setter
$ → Signal<Set<E>>: Available on Set<E>, provided by the SignalSetExtensions extension
Lift a primitive Set into a reactive Signal<Set<E>>.
no setter
autoDispose ↔ bool: Throws and error if read after dispose and can be disposed on last unsubscribe.
getter/setter pairinherited
debugLabel → String?: Debug label for Debug Mode Debug label for Debug Mode
no setterinherited
disposed ↔ bool: Check if the effect is disposed
getter/setter pairinherited
equalityCheck → SignalEquality<Set<E>>: Optional method to check if to values are the same
no setterinherited
first → E: The first element.
no setterinherited
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
globalId → int: finalinherited
hashCode → int: The hash code for this object.
no setteroverride
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
internalValue → Set<E>: @internal Internal getter for the raw value without subscription tracking.
no setterinherited
isEmpty → bool: Whether this collection has no elements.
no setterinherited
isInitialized → bool: Check if a signal value is set (does not subscribe)
no setterinherited
isNotEmpty → bool: Whether this collection has at least one element.
no setterinherited
iterator → Iterator<E>: A new Iterator that allows iterating the elements of this Iterable.
no setterinherited
last → E: The last element.
no setterinherited
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 setterinherited
name → String?: finalinherited
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 setterinherited
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
unwatched → void Function()?: finalinherited
value ↔ Set<E>: Gets the current value of the signal.
getter/setter pairinherited
version ↔ int: Version numbers should always be >= 0, because the special value -1 is used by Nodes to signify potentially unused but recyclable nodes.
getter/setter pairinherited
wait → Future<List<T>>: Available on Iterable<Future<T>>, provided by the FutureIterable extension
Waits for futures in parallel.
no setter
watched → void Function()?: finalinherited

Methods

add(E value) → bool: Available on Signal<Set<E>>, provided by the SetSignalExtension extension
add(E value) → bool: Adds value to the set.
inherited
addAll(Iterable<E> elements) → void: Available on Signal<Set<E>>, provided by the SetSignalExtension extension
addAll(Iterable<E> elements) → void: Adds all elements to this set.
inherited
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.
call() → Set<E>: Return the value when invoked
inherited
cast<R>() → Set<R>: Provides a view of this set as a set of R instances.
inherited
cast<R>() → Set<R>: Available on ReadonlySignal<Set<E>>, provided by the ReadonlySetSignalExtension extension
clear() → void: Available on Signal<Set<E>>, provided by the SetSignalExtension extension
clear() → void: Removes all elements from the set.
inherited
contains(Object? value) → bool: Whether the collection contains an element equal to element.
inherited
containsAll(Iterable<Object?> other) → bool: Whether this set contains all the elements of other.
inherited
containsAll(Iterable<Object?> other) → bool: Available on ReadonlySignal<Set<E>>, provided by the ReadonlySetSignalExtension extension
difference(Set<Object?> other) → Set<E>: Available on ReadonlySignal<Set<E>>, provided by the ReadonlySetSignalExtension extension
difference(Set<Object?> other) → Set<E>: Creates a new set with the elements of this that are not in other.
inherited
dispose() → void: Dispose the signal
inherited
elementAt(int index) → E: Returns the indexth 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<R>(Iterable<R> toElements(E element)) → Iterable<R>: Expands each element of this Iterable into zero or more elements.
inherited
firstWhere(bool test(E element), {E orElse()?}) → E: The first element that satisfies the given predicate test.
inherited
fold<R>(R initialValue, R combine(R previousValue, E element)) → R: 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 element)) → void: Invokes action on each element of this iterable in iteration order.
inherited
get() → Set<E>: Helper method to get the current value
inherited
internalRefresh() → bool: @internal Refreshes the signal's value internally.
inherited
intersection(Set<Object?> other) → Set<E>: Available on ReadonlySignal<Set<E>>, provided by the ReadonlySetSignalExtension extension
intersection(Set<Object?> other) → Set<E>: Creates a new set which is the intersection between this set and other.
inherited
join([String separator = ""]) → String: Converts each element to a String and concatenates the strings.
inherited
lastWhere(bool test(E element), {E orElse()?}) → E: The last element that satisfies the given predicate test.
inherited
lookup(Object? object) → E?: Available on ReadonlySignal<Set<E>>, provided by the ReadonlySetSignalExtension extension
lookup(Object? object) → E?: If an object equal to object is in the set, return it.
inherited
map<R>(R toElement(E e)) → Iterable<R>: The current elements of this iterable modified by toElement.
inherited
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
onDispose(void cleanup()) → void Function(): Add a cleanup function to be called when the signal is disposed
inherited
overrideWith(Set<E> val) → Signal<Set<E>>: Override the current signal with a new value as if it was created with it.
inherited
peek() → Set<E>: In the rare instance that you have an effect that should write to another signal based on the previous value, but you don't want the effect to be subscribed to that signal, you can read a signals's previous value via signal.peek().
inherited
readonly() → ReadonlySignal<Set<E>>: Returns a readonly signal
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: Available on Signal<Set<E>>, provided by the SetSignalExtension extension
remove(Object? value) → bool: Removes value from the set.
inherited
removeAll(Iterable<Object?> elements) → void: Removes each element of elements from this set.
inherited
removeAll(Iterable<Object?> elements) → void: Available on Signal<Set<E>>, provided by the SetSignalExtension extension
removeWhere(bool test(E element)) → void: Removes all elements of this set that satisfy test.
inherited
removeWhere(bool test(E element)) → void: Available on Signal<Set<E>>, provided by the SetSignalExtension extension
retainAll(Iterable<Object?> elements) → void: Removes all elements of this set that are not elements in elements.
inherited
retainAll(Iterable<Object?> elements) → void: Available on Signal<Set<E>>, provided by the SetSignalExtension extension
retainWhere(bool test(E element)) → void: Removes all elements of this set that fail to satisfy test.
inherited
retainWhere(bool test(E element)) → void: Available on Signal<Set<E>>, provided by the SetSignalExtension extension
set(Set<E> val, {bool force = false}) → bool: Updates the signal's value by method call.
inherited
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 value)) → Iterable<E>: Creates an Iterable that skips leading elements while test is satisfied.
inherited
subscribe(void fn(Set<E> value)) → void Function(): Subscribe to value changes with a dispose function
inherited
subscribeToNode(Node node) → void: @internal Subscribes this signal to notifications from a given dependency node.
inherited
take(int count) → Iterable<E>: Creates a lazy iterable of the count first elements of this iterable.
inherited
takeWhile(bool test(E value)) → Iterable<E>: Creates a lazy iterable of the leading elements satisfying test.
inherited
toJson() → dynamic: Convert value to JSON
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
toSignal({SetSignalOptions<T>? options, bool? autoDispose, String? debugLabel}) → SetSignal<T>: Available on Set<T>, provided by the SignalSetUtils extension
Convert this existing Set to a reactive SetSignal.
toSignal({IterableSignalOptions<T>? options, bool? autoDispose, String? debugLabel}) → IterableSignal<T>: Available on Iterable<T>, provided by the SignalIterableUtils extension
Convert an existing Iterable to an IterableSignal.
toString() → String: A string representation of this object.
inherited
union(Set<E> other) → Set<E>: Creates a new set which contains all the elements of this set and other.
inherited
union(Set<E> other) → Set<E>: Available on ReadonlySignal<Set<E>>, provided by the ReadonlySetSignalExtension extension
unsubscribeFromNode(Node node) → void: @internal Unsubscribes this signal from notifications from a given dependency node.
inherited
where(bool test(E element)) → Iterable<E>: Creates a new lazy Iterable with all elements that satisfy the predicate test.
inherited
whereType<R>() → Iterable<R>: Creates a new lazy Iterable with all elements that have type T.
inherited

Operators

operator &(Set<E> other) → SetSignal<E>: Fork: create a new signal with value is the concatenation of source signal and iterable parameter
operator <<(Set<E> other) → SetSignal<E>: Inject: Update current signal value with iterable
operator ==(Object other) → bool: The equality operator.
override
operator |(Signal<Iterable<E>> other) → SetSignal<E>: Pipe: create a new signal by sending value from source to other