queue.io

library2.3.0jsnpmunverified

Event-based queue iteration library for JavaScript (v2.3.0). Allows creating asynchronously filled queues from event emitters or iterables, then iterating over them with forward/backward directions. Supports appending, prepending (listen), and intercepting queues. Key differentiator: queues can be populated before or after iterators are created, and multiple independent iterators can traverse the same queue in different directions. Depends on Node.js EventEmitter. Not heavily maintained (last update years ago).

storage

npm install queue.io

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · QUEUE.IO

queue.io

storagejavascriptv2.3.0

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

Queue

✓ import Queue from 'queue.io'

✗ const Queue = require('queue.io')

Default export; ESM import preferred.

Queue

✓ const Queue = require('queue.io').default

✗ const Queue = require('queue.io')

In CommonJS, the default export is accessed via .default.

Queue.NEXT

✓ import Queue from 'queue.io'; Queue.NEXT

✗ import { NEXT } from 'queue.io'

NEXT and PREV are static properties on the Queue class, not named exports.

Creates a queue from an EventEmitter, pushes values, then iterates forward consuming until done.

import Queue from 'queue.io'; import { EventEmitter } from 'events'; const emitter = new EventEmitter(); const queue = Queue(emitter, 'value'); emitter.emit('value', 1); emitter.emit('value', 2); emitter.emit('value', 3); emitter.emit('done'); const iterator = queue.iterate(); iterator.on('value', (data) => { console.log('Value:', data.value); if (data.value < 3) { data.next(); } }); iterator.on('done', () => { console.log('Iteration done'); });

Debug

Known issues

deprecatedThe package uses an older EventEmitter pattern; consider using async iterators for modern code.

fix

Use native async iteration with for-await-of or libraries like iter-ops.

affects: >=0.0.0

gotchaQueue.from does not accept generic iterables (only array-like objects). Passing a Set or Map may not work as expected.

fix

Convert iterables to arrays first: Queue.from([...set]).

affects: >=2.0.0

gotchaIf no eventEmitter is provided, the queue auto-dones at next tick only if no queues are joined via intercept/listen/append. This can cause premature done if not joined.

fix

Always provide an eventEmitter or use Queue.from to avoid unexpected done.

affects: >=2.0.0

Errors

Common errors & fixes

TypeError: queue.iterate is not a function

Importing incorrectly in ESM or CJS environment.

fix

Ensure you are using the default export: import Queue from 'queue.io' then call Queue() to create a queue.

Uncaught TypeError: Cannot read properties of undefined (reading 'on')

Calling iterator.on before queue has been filled and done.

fix

Call iterate() only after the queue is done, or ensure events are listened after iterator creation.

Error: done event must be emitted on the eventEmitter

Forgetting to emit 'done' on the eventEmitter when using custom emitter.

fix

Emit emitter.emit('done') after all values are pushed.

Upgrade

Version history

2.3.0latest on npm

Audit

Dependencies

eventsoptionalUses Node.js EventEmitter as optional event source

Agent activity

17 hits · last 30 days

node

OpenAI (training)

Resources

githubgit://github.com/Lcfvs/queue.io ↗

packagequeue.io ↗

homepagehttps://github.com/Lcfvs/ ↗