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@ue-too/board / SynchronousObservable

Class: SynchronousObservable<T> ​

Defined in: packages/board/src/utils/observable.ts:210

Synchronous Observable implementation that notifies observers immediately.

Remarks ​

This Observable calls all observers synchronously and immediately when notify() is called. The notify method doesn't return until all observers have executed.

Use SynchronousObservable when:

  • You need immediate, guaranteed execution of observers
  • Observer execution order matters and must be predictable
  • You're in a performance-critical path (no async overhead)

Caution: Can lead to recursion issues if observers trigger notifications.

Example ​

typescript
const observable = new SynchronousObservable<[string]>();

observable.subscribe((message) => {
  console.log('Observer received:', message);
});

console.log('Before notify');
observable.notify('Hello');
console.log('After notify');

// Output:
// Before notify
// Observer received: Hello
// After notify

See ​

AsyncObservable for asynchronous notifications

Type Parameters ​

T ​

T extends any[]

Tuple type of data emitted to observers

Implements ​

Constructors ​

Constructor ​

new SynchronousObservable<T>(): SynchronousObservable<T>

Returns ​

SynchronousObservable<T>

Methods ​

notify() ​

notify(...data): void

Defined in: packages/board/src/utils/observable.ts:262

Notifies all observers with the provided data synchronously.

Parameters ​

data ​

...T

The data to pass to all observers

Returns ​

void

Remarks ​

Each observer is called immediately in order. This method blocks until all observers have completed execution.

Implementation of ​

Observable.notify

subscribe() ​

subscribe(observer, options?): () => void

Defined in: packages/board/src/utils/observable.ts:224

Subscribes an observer to receive notifications.

Parameters ​

observer ​

Observer<T>

The callback function to be notified

options? ​

SubscriptionOptions

Optional subscription options including AbortSignal

Returns ​

Unsubscribe function to remove this observer

(): void

Returns ​

void

Remarks ​

If an AbortSignal is provided and is already aborted, the observer is not added and the returned unsubscribe function is a no-op.

Implementation of ​

Observable.subscribe