API reference

Six surfaces.
One fluent class.

All dispatch is synchronous. Public mutators return the same instance. Event types must be strings; registration handlers are validated immediately.

EventPubSub public API
Member	Signature	Contract	Returns
`on`	`on(type, handler, once = false)`	Registers a function. `*` creates a wildcard subscription.	`this`
`once`	`once(type, handler)`	Registers a record removed immediately before its first invocation.	`this`
`off`	`off(type = '', handler = '')`	Removes all matching function registrations, or the whole type when handler is exactly ``. A missing type returns before optional-handler validation, preserving 5.x behavior. Only the public string `` maps to the internal wildcard Symbol; `Symbol(event-pubsub-all)` remains an ordinary typed name.	`this`
`emit`	`emit(type, ...payload)`	Runs wildcard then typed handlers synchronously over live registration arrays; appended handlers can run in the current emit.	`this`
`reset`	`reset()`	Clears every typed and wildcard registration.	`this`
`list`	`get list()`	Returns an isolated null-prototype object snapshot of topic arrays. Wildcards use `Symbol.for('event-pubsub-all')`.	`object`

Typed subscriber

const handler = (payload) => {
    console.log(payload);
};

events.on('topic', handler);
events.emit('topic', { id: 1 });
events.off('topic', handler);

Wildcard subscriber

events.on('*', (type, ...payload) => {
    console.log(type, payload);
});

events.emit('topic', { id: 1 });
events.off(); // wildcard subscribers only

Synchronous exceptions are publisher-visible.

A synchronously thrown handler stops the current dispatch and propagates through emit. A one-shot registration is removed immediately before its own invocation, so reached one-shot handlers stay removed; unvisited registrations remain. Persistent handlers remain registered. Handler return values and promises are ignored, so callers must handle asynchronous rejections in application code.