@statesync/persistence

---

@statesync/persistence / withCrossTabSync

Function: withCrossTabSync()

function withCrossTabSync<T>(storage, options): object;

Defined in: persistence/src/cross-tab.ts:335

Wraps a storage backend's save method to automatically broadcast snapshots to other tabs after each successful save.

This is a lower-level utility for cases where you want cross-tab sync without using the full createPersistenceApplier. The returned object exposes both the wrapped save function and the underlying CrossTabSync instance for manual control.

Type Parameters

Type Parameter	Description
T	The shape of the application state.

Parameters

Parameter	Type	Description
storage	{ save: Promise<void>; }	Any object with a save method (typically a StorageBackend).
storage.save	-
options	CrossTabSyncHandlers<T>	Cross-tab sync configuration and event handlers.

Returns

object

An object with a save method (broadcasts after writing) and a crossTab property for direct access to the sync manager.

crossTab

crossTab: CrossTabSync<T>;

save()

save(snapshot): Promise<void>;

Parameters

Parameter	Type
snapshot	SnapshotEnvelope<T>

Returns

Promise<void>

Example

const { save, crossTab } = withCrossTabSync(
  createLocalStorageBackend({ key: 'my-state' }),
  {
    channelName: 'my-app-state',
    onSnapshot: (snapshot) => applier.apply(snapshot),
  },
);

await save(snapshot); // Saves to storage AND broadcasts to other tabs
crossTab.dispose();   // Cleanup when done