Pulse (pulse-ts)

Pulse is a tiny, developer-friendly TypeScript-first event emitter with a minimal, well-typed API for both quick untyped usage and production-grade TypeScript event maps.

Install

# npm
npm install pulse-ts

# yarn
yarn add pulse-ts

# pnpm
pnpm add pulse-ts

Known example — counterPulse

import { createPulse } from 'pulse-ts';

export const counterPulse = createPulse();

counterPulse.on('counter:incremented', (counter) => {
  console.log(`Counter: ${counter.count}`);

  if (counter.count >= 10) {
    console.log('Reached 10, unsubscribing');
    counterPulse.unsubscribe('counter:incremented');
  }
});

Quick examples

• one-time listener (auto-unsubscribe after first emit)

const p = createPulse<{ 'ready': void }>();
p.once('ready', () => console.log('ready fired once'));
await p.emit('ready', undefined);

• clear all listeners

p.clear();

API

• createPulse() — create a typed Pulse instance
  • p.on(event, handler) — register a handler; returns an unsubscribe function for that handler
  • p.once(event, handler) — register a handler that is removed automatically after first emit
  • p.off(event, handler) — remove a specific handler
  • p.unsubscribe(event) — remove all handlers for an event
  • p.offAll(event) — alias for unsubscribe(event)
  • p.clear() — remove all handlers across all events
  • p.emit(event, payload) — emit an event; handlers may be async
• pulse — default untyped singleton for quick use
• defineEvent(name, handler) — register handler and return an unsubscribe function
• createListener(pulse, handlers) — register multiple handlers and return { off() }
• Types: EventMap, HandlerFor — helpers for typing handlers

Notes

• Emissions are async-friendly; handlers can return promises.
• Small, dependency-free, and focused on type safety and ergonomics.

Contributing

PRs and issues welcome. Run tests and follow existing project formatting.

MIT LICENSE