Errors — Async

Source: Errors.ts

All error classes in this module extend UtilityError from @litert/utils-ts-types, which provides a context property for structured error details and an origin property for the original cause.

Import

import { E_TIMEOUT, E_ABORTED, E_FIBER_EXITED } from '@litert/utils-async';

---

E_TIMEOUT

Thrown when an asynchronous operation exceeds its configured timeout. Extends UtilityError<IAsyncErrorContext>.

class E_TIMEOUT extends UtilityError<IAsyncErrorContext> {
    readonly name: 'timeout';
    readonly message: 'Operation timed out.';
    readonly unresolvedPromise?: Promise<unknown>;

    constructor(ctx?: IAsyncErrorContext, origin?: unknown);
}

Properties

• unresolvedPromise?: Promise<unknown>

  A reference to the still-pending Promise when the timeout fired, if provided in the context. Use this to track or collect the eventual result of the original task.

Usage

import { withTimeout, E_TIMEOUT } from '@litert/utils-async';

try {
    await withTimeout(1000, fetch('https://example.com/slow'));
} catch (e) {
    if (e instanceof E_TIMEOUT) {
        console.error('Timed out after 1 second');
        console.log('Still pending:', e.unresolvedPromise);
    }
}

---

E_ABORTED

Thrown when an asynchronous operation is cancelled via an AbortSignal. Extends UtilityError<IAsyncErrorContext>.

class E_ABORTED extends UtilityError<IAsyncErrorContext> {
    readonly name: 'aborted';
    readonly message: 'Operation aborted.';

    constructor(context?: IAsyncErrorContext, origin?: unknown);

    static isAbortedError(v: unknown): boolean;
}

NOTE

instanceof E_ABORTED also returns true for standard DOMException instances with name === 'AbortError', via Symbol.hasInstance. Use E_ABORTED.isAbortedError(v) for portable checks that cover both cases.

Static Methods

• E_ABORTED.isAbortedError(v: unknown): boolean

  Returns true if v is an instance of E_ABORTED or a standard AbortError (a DOMException with name === 'AbortError'). Useful for portably handling abort errors regardless of origin.

Usage

import { sleep, E_ABORTED } from '@litert/utils-async';

const ac = new AbortController();
setTimeout(() => ac.abort(), 500);

try {
    await sleep(2000, ac.signal);
} catch (e) {
    if (e instanceof E_ABORTED) {
        console.log('Sleep was aborted');
    }
}

---

E_FIBER_EXITED

Thrown when attempting to resume or interact with a fiber (FiberController) that has already finished execution. Extends UtilityError<IAsyncErrorContext>.

class E_FIBER_EXITED extends UtilityError<IAsyncErrorContext> {
    readonly name: 'fiber_exited';
    readonly message: 'Fiber has already exited.';

    constructor(context?: IAsyncErrorContext, origin?: unknown);
}

Usage

import { FiberController, E_FIBER_EXITED } from '@litert/utils-async';

const fiber = new FiberController({ main: async (ctx) => { /* ... */ } });
await fiber.waitForExit();

try {
    fiber.resume(); // Fiber already exited
} catch (e) {
    if (e instanceof E_FIBER_EXITED) {
        console.error('Cannot resume: fiber has already exited');
    }
}