API reference › @evolu/common › Task › Mutex

Defined in: packages/common/src/Task.ts:2737

A mutex (mutual exclusion) that ensures only one Task runs at a time.

This is a specialized version of a Semaphore with a permit count of 1.

Example

await using run = createRun();

const mutex = createMutex();

const task =
  (id: string): Task<void> =>
  async (run) => {
    const { console } = run.deps;
    console.log("start", id);
    await run(sleep("10ms"));
    console.log("end", id);
    return ok();
  };

await Promise.all([
  run(mutex.withLock(task("1"))),
  run(mutex.withLock(task("2"))),
]);

// start 1
// end 1
// start 2
// end 2

Extends

Methods

[dispose]()

dispose: void;

Defined in: node_modules/.bun/typescript@5.9.3/node_modules/typescript/lib/lib.esnext.disposable.d.ts:36

Inherited from

Disposable.[dispose]

Properties

snapshot

readonly snapshot: () => SemaphoreSnapshot;

Defined in: packages/common/src/Task.ts:2747

Returns the current mutex state for monitoring/debugging.

withLock

readonly withLock: <T, E, D>(task: Task<T, E, D>) => Task<T, E, D>;

Defined in: packages/common/src/Task.ts:2744

Executes a Task while holding the mutex lock.

Only one Task can hold the lock at a time. Other Tasks wait until the lock is released.

Markdown for LLMs