Nano Events

Simple and tiny event emitter library for JavaScript.

• Only 108 bytes (minified and brotlied). It uses Size Limit to control size.
• The on method returns unbind function. You don’t need to save callback to variable for removeListener.
• TypeScript and ES modules support.
• No aliases, just emit and on methods. No Node.js EventEmitter compatibility.

import { createNanoEvents } from 'nanoevents'

const emitter = createNanoEvents()

const unbind = emitter.on('tick', volume => {
  summary += volume
})

emitter.emit('tick', 2)
summary //=> 2

unbind()
emitter.emit('tick', 2)
summary //=> 2

Made at Evil Martians, product consulting for developer tools.

Docs

Read full docs here.

Change Log

This project adheres to Semantic Versioning.

9.1.0

• Added EmitterMixin type (by @fuadsaud).

9.0

• Dropped Node.js 16 support.
• Reduced size (by @igisev).

8.0

• Dropped Node.js 14 support.
• Fixed types (by @jakub791).

7.0.1

• Reduced size.

7.0

• Improved performance (by Sergey Ukustov).
• Dropped Node.js 12 support.

6.0.2

• Reduced npm package size.

6.0.1

• Fixed package.json export (by Jules Robichaud-Gagnon).

6.0

• Moved project to ESM-only type. Applications must use ESM too.
• Dropped Node.js 10 support.

5.1.13

• Added default to package.exports.

5.1.12

• Reduced npm package size.

5.1.11

• Fixed unsubscribing on cleaned Emitter#events (by Mikhail Nasyrov).

5.1.10

• Fixed package.types path.

5.1.9

• Added package.types.

5.1.8

• Fix ES module support.

5.1.7

• Simplify Emitter type usage.

5.1.6

• Clean up code.

5.1.5

• Fix ES module regression.

5.1.4

• Remove React Native extra files.

5.1.3

• Allow to use library in React Native without resolverMainFields.

5.1.2

• Fix React Native warnings.

5.1.1

• Add temporary workaround for React Native.

5.1

• Add Unsubscribe type.

5.0.1

• Mark package to be free from side effects.
• Clean up types (by Bogdan Chadkin).

5.0

• Use named export instead of default export.

4.0.3

• Add this type definition (by Anton Khlynovskiy).
• Improve docs (by @azu and @38elements).

4.0.2

• Improve emit performance.

4.0.1

• Reduce size (by Eduardo San Martin Morote).

4.0

• Use index.js instead of index.mjs for ES modules.

3.0

• Use modern JS syntax and drop IE 11 support.
• Remove nanoevents/unbind-all helper.
• Add NanoEvents#set.
• Add TypeScript definitions.
• Add ES modules support.
• Reduce size.

2.0

• Remove this from listeners to bind it explicitly (by Alexander Zonov).

1.0.8

• Reduce size (by Vladlen Grachev).

1.0.7

• Reduce size (by Vladlen Grachev).

1.0.6

• Fix docs.

1.0.5

• Reduce npm package size.

1.0.4

• Reduce npm package size.

1.0.3

• Reduce npm package size.

1.0.2

• Reduce size (by Anton Khlynovskiy).

1.0.1

• Reduce size (by Anton Khlynovskiy).

1.0

• Remove NanoEvents#once method.
• NanoEvents#emit doesn’t return boolean anymore.
• Check arguments types only in development.
• Reduce size.

0.4.1

• Fix clashing with Object methods (by Anton Khlynovskiy).
• Reduce size (by Anton Khlynovskiy).

0.4

• Add nanoevents/unbind-all helper (by Igor Deryabin).
• Fix JSDoc (by Igor Deryabin).
• Reduce size.

0.3

• Allow to change listeners during the emit.

0.2

• Throw a error on non-function listener.

0.1

• Initial release.