purplejs/src/dom/add-props-and-events/add-event.ts

A little bit of React

import ElementObject from '../../interfaces/element-object'
import HTMLElement from '../../interfaces/html-element'

export default (
  element: ElementObject,
  dom: HTMLElement,
  key: string,
): void => {
  const eventType = key.toLowerCase().substring(2);
  dom.addEventListener(eventType, element[key]);
}