Class MapStore<T>

Internal_dead

Internal_subscriberCounts

Internal_subscribers

Internalid

_sendEvent

• _sendEvent(event: StoreEvent<Store<Record<string, T>>>): void
  Internal

  Sends an event to all subscribers if the store has not been disposed of.

  Parameters

  • event: StoreEvent<Store<Record<string, T>>>

  Returns void

any

• any(fn: AnySubscriber<Store<Record<string, T>>>): void

  Subscribes the provided function to all store events. This is a convenience method that registers the function for 'change', 'append', 'clear', and 'deletion' events.

  Parameters

  • fn: AnySubscriber<Store<Record<string, T>>>

    A callback function that will be called for all store events

  Returns void

  void

current

• current(): Record<string, T>

  Get a deep clone of the current store value.

  Added in 4.0.0-rc15 as the recommended way to access store values since the value property is now protected.

  Returns Record<string, T>

  A deep clone of the store's current value

  Example

  const user = store({ value: { name: "John", age: 30 } });
  const userData = user.current();  // { name: "John", age: 30 }
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dispose

• dispose(): void

  Close the store so it no longer sends events.

  Returns void

on

• on<K extends "clear" | "change" | "append" | "update" | "deletion">(
      type: K,
      fn: EventSubscriber<K, Store<Record<string, T>>>,
      callNow?: true,
  ): number

  Add an event listener to the store.

  Type Parameters

  • K extends "clear" | "change" | "append" | "update" | "deletion"

  Parameters

  • type: K

    The type of event to listen for. Supported event types include:

    • update: Triggered when the store's value is updated via update().
    • append: For ListStore - Triggered when an item is added to the list.
    • deletion: For ListStore/MapStore - Triggered when an item is removed.
    • change: For ListStore/MapStore: Triggered when an item at an index/key has its value set via the corresponding store's set() method.
    • 'clear': Triggered when the store is cleared.
  • fn: EventSubscriber<K, Store<Record<string, T>>>

    A callback function that will be invoked when the specified event occurs. The function receives a StoreEvent object with details about the event.
  • OptionalcallNow: true

    Optional parameter to immediately trigger the callback with current value

  Returns number

  A unique subscriber ID that can be used to unsubscribe the listener.

  Example

  // Subscribe to updates
  const counter = store({ value: 0 });
  counter.on("update", (event) => {
    console.log(`Counter updated to: ${event.value}`);
  });
  
  // Subscribe and trigger immediately with current value
  counter.on("update", (event) => {
    console.log(`Current value: ${event.value}`);
  }, true);
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unsubscribe

• unsubscribe(
      type: "clear" | "change" | "append" | "update" | "deletion",
      id: number,
  ): void

  Removes a specific event listener from the store.

  Parameters

  • type: "clear" | "change" | "append" | "update" | "deletion"

    The type of event from which to unsubscribe.
  • id: number

    The subscriber ID returned by the on() method when the listener was registered.

  Returns void

  Throws

  Will throw an error if the subscriber ID is invalid or not found.

update

• update(value: (arg: Record) => Record): null | Record<string, T>

  Updates the store's value and notifies all subscribers.

  As of 4.0.0-rc15, this method can also accept a transform function that receives the current value and returns a new value.

  Parameters

  • value: (arg: Record) => Record

    The new value to set for the store, or a transform function that takes the current value and returns a new value.

  Returns null | Record<string, T>

  The updated value, or null if the store has been disposed.

  Emits

  'update' event with the new value when successfully updated.

  Example

  // Direct update
  counter.update(5);
  
  // Update using a transform function
  counter.update(current => current + 1);
  
  // Complex transform
  userStore.update(user => ({
    ...user,
    visits: user.visits + 1,
    lastVisit: new Date()
  }));
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• update(value: Record): null | Record<string, T>

  Updates the store's value and notifies all subscribers.

  As of 4.0.0-rc15, this method can also accept a transform function that receives the current value and returns a new value.

  Parameters

  • value: Record

    The new value to set for the store, or a transform function that takes the current value and returns a new value.

  Returns null | Record<string, T>

  The updated value, or null if the store has been disposed.

  Emits

  'update' event with the new value when successfully updated.

  Example

  // Direct update
  counter.update(5);
  
  // Update using a transform function
  counter.update(current => current + 1);
  
  // Complex transform
  userStore.update(user => ({
    ...user,
    visits: user.visits + 1,
    lastVisit: new Date()
  }));
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valueOf

• valueOf(): Record<string, T>

  Returns Record<string, T>

  Deprecated

  Use current() instead

StaticisUpdater

• isUpdater<T>(val: unknown): val is (arg: T) => T
  Internal

  Utility method to check if a value is a transform function

  Type Parameters

  • T

  Parameters

  • val: unknown

  Returns val is (arg: T) => T