Simple, small eventhandler for any ts project

eventhandler.ts

// Event types have a namespace to aid in finding bugs
export enum EventType {
    EXAMPLE = 'namespace:example',
}

const EventHandler = {
    callbacks: {} as { [key in EventType]: { [id: string]: Function }},
    on: (callerSig: string, type: EventType, callback: Function) => {
        if (!EventHandler.callbacks[type]) {
            EventHandler.callbacks[type] = {};
        }

        EventHandler.callbacks[type][callerSig] = callback;
    },
    once: (callerSig: string, type: EventType, callback: Function) => {
        const onceCallback = (...args: any[]) => {
            EventHandler.off(callerSig, type);
            callback(...args);
        };

        EventHandler.on(callerSig, type, onceCallback);
    },
    off: (callerSig: string, type: EventType) => {
        if (EventHandler.callbacks[type]) {
            delete EventHandler.callbacks[type][callerSig];
        }
    },
    emit: (type: EventType, ...args: any[]) => {
        if (EventHandler.callbacks[type]) {
            Object.values(EventHandler.callbacks[type]).forEach(callback => {
                callback(...args);
            });
        }
    },
    emitExcept: (type: EventType, exceptCallerSigs: string[], ...args: any[]) => {
        if (EventHandler.callbacks[type]) {
            Object.entries(EventHandler.callbacks[type]).forEach(([callerSig, callback]) => {
                if (!exceptCallerSigs.includes(callerSig)) {
                    callback(...args);
                }
            });
        }
    }
};

export default EventHandler;