Class method utilities

Signatures, arguments, and exceptions for the decorators and functions provided by the asyncmux default export.

asyncmux is the default export. It can be used both as a class method decorator and as a function.

import { asyncmux } from "asyncmux";

Decorator @asyncmux

Applies a write lock to the target async class method.

function asyncmux<TMethod extends (this: any, ...args: any) => Promise<any>>(
  method: TMethod,
  context: unknown,
): TMethod;

The return value is the method with lock acquisition and release built in. Each call acquires the write lock of this and releases it when the method finishes.

• Throws ReentrantLockError when reentrancy is detected.
• Throws DecoratorSupportError without Stage 3 decorator support.

Function asyncmux()

Acquires the write lock of the given object.

function asyncmux(this_: object, signal?: AbortSignal): Promise<AsyncmuxLock>;

The return value is a Promise that resolves with the acquired AsyncmuxLock. For how to release it, see AsyncmuxLock.

• Throws ReentrantLockError synchronously when reentrancy is detected. No detection occurs outside a lock context established by a decorator.
• Functions cannot be lock targets. When the first argument is a function, it is treated as a decorator.

Decorator @asyncmux.readonly

Applies a read lock to the target async class method. The signature and arguments are the same as @asyncmux.

function asyncmux.readonly<
  TMethod extends (this: any, ...args: any) => Promise<any>,
>(
  method: TMethod,
  context: unknown,
): TMethod;

Read locks can run concurrently with each other. They wait while a write lock is held. The return value and exceptions are the same as @asyncmux.

Function asyncmux.readonly()

Acquires the read lock of the given object.

function asyncmux.readonly(
  this_: object,
  signal?: AbortSignal,
): Promise<AsyncmuxLock>;

The arguments and return value are the same as asyncmux(); only the lock kind differs.

See also

• Decorators
• Manual locking
• Concurrency model