Signals

A signal is an event that doesn't send any data. To create such event, use type void explicitly:

class Signal extends SubEvent<void> {} // reusable Signal type

const s = new Signal(); // creating event-signal

s.emit(); // emitting the signal

And when you need to pass in options, your data will have to be null or undefined:

s.emit(null, {schedule: EmitSchedule.next});

s.emit(undefined, {schedule: EmitSchedule.next});

Or you can implement your own, signal-specific trigger method:

import {SubEvent, IEmitOptions} from 'sub-events';

class Signal extends SubEvent<void> {

    trigger(options?: IEmitOptions) {
        return this.emit(undefined, options);
    }
}

When listening for a once-off signal, see also methods once and toPromise.