Classevent-emitterv0.1.0-next.0

TypedEventEmitter

Typed, cross-runtime event emitter with per-event tuple payloads.

class TypedEventEmitter<TEvents extends EventMap<TEvents>>

class TypedEventEmitter<TEvents extends EventMap<TEvents>>

Member visibility

Filter class members by access level.

Showing members with Protected visibility and higher.

Methods

emit()
eventNames()
listenerCount()
off()
on()
once()
removeAllListeners()
removeListener()
waitFor()

TEvents

Map of event names to readonly tuple payloads.

TEvents extends EventMap<TEvents>

TEvents extends EventMap<TEvents>

emit()

Emits an event, invoking each listener with the payload tuple. Returns true when the event had listeners.

public emit<TEventKey>(
    event: TEventKey,
    args: TEvents[TEventKey]
): boolean

public emit<TEventKey>(
    event: TEventKey,
    args: TEvents[TEventKey]
): boolean

eventNames()

Returns the event names with at least one listener.

public eventNames(): EventKey<TEvents>[]

public eventNames(): EventKey<TEvents>[]

listenerCount()

Counts the listeners registered for an event.

public listenerCount<TEventKey>(event: TEventKey): number

public listenerCount<TEventKey>(event: TEventKey): number

off()

Removes a previously registered listener.

public off<TEventKey>(
    event: TEventKey,
    listener: (...args: TEvents[TEventKey]) => void
): this

public off<TEventKey>(
    event: TEventKey,
    listener: (...args: TEvents[TEventKey]) => void
): this

on()

Registers a persistent listener for an event.

public on<TEventKey>(
    event: TEventKey,
    listener: (...args: TEvents[TEventKey]) => void
): this

public on<TEventKey>(
    event: TEventKey,
    listener: (...args: TEvents[TEventKey]) => void
): this

once()

Registers a listener removed after its first invocation.

public once<TEventKey>(
    event: TEventKey,
    listener: (...args: TEvents[TEventKey]) => void
): this

public once<TEventKey>(
    event: TEventKey,
    listener: (...args: TEvents[TEventKey]) => void
): this

removeAllListeners()

Removes every listener for an event, or for all events when no event is given.

public removeAllListeners(
    event?: EventKey<TEvents>
): this

public removeAllListeners(
    event?: EventKey<TEvents>
): this

removeListener()

Alias of offoff.

public removeListener<TEventKey>(
    event: TEventKey,
    listener: (...args: TEvents[TEventKey]) => void
): this

public removeListener<TEventKey>(
    event: TEventKey,
    listener: (...args: TEvents[TEventKey]) => void
): this

waitFor()

Waits for the next emission of an event, resolving with its payload tuple. With a filter, resolves on the first payload the filter accepts.

public async waitFor<TEventKey>(
    event: TEventKey,
    options?: WaitForOptions<TEvents[TEventKey]>
): Promise<TEvents[TEventKey]>

public async waitFor<TEventKey>(
    event: TEventKey,
    options?: WaitForOptions<TEvents[TEventKey]>
): Promise<TEvents[TEventKey]>

Parameter: event

The event to wait for.

Parameter: options

An optional filter, abort signal, and timeout.

const ee = new TypedEventEmitter<{ ping: [n: number] }>();
const pending = ee.waitFor('ping', { filter: n => n > 0, timeoutMs: 1000 });
ee.emit('ping', -1); // ignored by filter
ee.emit('ping', 42); // resolves pending with [42]

const ee = new TypedEventEmitter<{ ping: [n: number] }>();
const pending = ee.waitFor('ping', { filter: n => n > 0, timeoutMs: 1000 });
ee.emit('ping', -1); // ignored by filter
ee.emit('ping', 42); // resolves pending with [42]