ReactiveX/rxjs · error · TypeError

Subscriber.error requires an error

Error message

Subscriber.error requires an error

What it means

Error "Subscriber.error requires an error" thrown in ReactiveX/rxjs.

Source

Thrown at packages/observable-polyfill/src/index.ts:223

  next(value: T): void {
    this.#assertBrand();
    if (arguments.length === 0) {
      throw new TypeError('Subscriber.next requires a value');
    }

    if (this.active) {
      const observers = Array.from(this.#observerList);
      for (const observer of observers) {
        observer.next(value);
      }
    }
  }

  error(error: any): void {
    this.#assertBrand();
    if (arguments.length === 0) {
      throw new TypeError('Subscriber.error requires an error');
    }

    this[errorSubscriber](error, true);
  }

  [errorSubscriber](error: any, hasSourceLocation: boolean): void {
    if (!this.active) {
      reportError(error, hasSourceLocation);
      return;
    }

    const observers = Array.from(this.#observerList);
    this[closeSubscriber](error);
    for (const observer of observers) {
      observer.error(error, hasSourceLocation);
    }
  }

View on GitHub (pinned to 54796b38a5)

When it happens

Trigger: Thrown at packages/observable-polyfill/src/index.ts:223 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of ReactiveX/rxjs@54796b38a5 (2026-08-28). Data as JSON: /api/errors/747a9407e6359e74. Report an issue: GitHub.