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Handling disposal in async code ​

Problem ​

Implement handling disposal in async code in a production-friendly way with @vielzeug/eventit while keeping setup and cleanup explicit.

Runnable Example ​

The snippet below is copy-paste runnable in a TypeScript project with @vielzeug/eventit installed.

Use BusDisposedError for instanceof checks instead of string matching:

ts
import { BusDisposedError } from '@vielzeug/eventit';

async function waitForLogin(bus: Bus<AppEvents>) {
  try {
    const { userId } = await bus.wait('user:login', AbortSignal.timeout(10_000));
    return userId;
  } catch (err) {
    if (err instanceof BusDisposedError) return null; // bus torn down — graceful exit
    throw err; // timeout or unexpected error — propagate
  }
}

Expected Output ​

  • The example runs without type errors in a standard TypeScript setup.
  • The main flow produces the behavior described in the recipe title.

Common Pitfalls ​

  • Forgetting cleanup/dispose calls can leak listeners or stale state.
  • Skipping explicit typing can hide integration issues until runtime.
  • Not handling error branches makes examples harder to adapt safely.