Typescript snippets

event.ts

export declare type EventCallback<T> = (arg: T) => any;
export declare type Event<T = any> = EventCallback<T>[];
export function emit<T>(e: Event<T>, data: T) {
  e.forEach(callback => callback(data))
}

hooks.ts

import { useEffect } from "react";

export function useDocumentEvent<K extends keyof DocumentEventMap>(type: K,
    listener: (this: Document, ev: DocumentEventMap[K]) => any,
    deps = []
) {

    useEffect(() => {
        document.addEventListener(type, listener);

        return () => {
            document.removeEventListener(type, listener);
        }

    }, deps)

}



export function useWindowEvent<K extends keyof WindowEventMap>(type: K,
    listener: (this: Window, ev: WindowEventMap[K]) => any,
    deps = []
) {

    useEffect(() => {
        window.addEventListener(type, listener);

        return () => {
            window.removeEventListener(type, listener);
        }

    }, deps)

}