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HTML

              
                <body>
  
  <h1>My TODO List</h1>
  <div id="my-react-app"></div>
</body>
              
            
!

CSS

              
                
              
            
!

JS

              
                const MyReact = importMyReact();

/** @jsx MyReact.createElement */

const element = <div>
        <ul>
          <li>Custom JSX parser</li>
          <li>Add Babel</li>
          <li>Add webpack</li>
          <li>Conquer React</li>
          <li>Conquer World</li>
        </ul>
      </div>;

MyReact.render(element, document.getElementById("my-react-app"));

//======================================
// **************MYREACT****************
//======================================

function importMyReact(){
  const TEXT_ELEMENT = "TEXT_ELEMENT";
  
  function render(element, parent) {
  // Get the props and type from element object
  const { type, props } = element;

  // Check if it is a text element
  const isTextElement = type === "TEXT_ELEMENT";

  // Create a new dom element
  const dom = !isTextElement
    ? document.createElement(type)
    : document.createTextNode(props.nodeValue);

  // Filter for eventListeners in the props
  const isListener = name => name.startsWith("on");

  // Add eventListeners to the dom element
  Object.keys(props)
    .filter(isListener)
    .forEach(name => {
      const eventType = name.toLowerCase().substring(2);
      dom.addEventListener(eventType, props[name]);
    });

  const isAttribute = name => !isAttribute && name !== "children";

  Object.keys(props)
    .filter(isAttribute)
    .forEach(name => {
      dom[name] = props[name];
    });

  // Check if there are any childrens of the given element
  const childElements = props.children || [];

  // render those childrens recursively first
  childElements.forEach(el => render(el, dom));

  // finally append the element to the parent element
  parent.appendChild(dom);
}

  function createElement(type, config, ...args) {
    const props = Object.assign({}, config);
    const hasChildren = args.length > 0;

    const allChildren = hasChildren ? [].concat(...args) : [];

    props.children = allChildren
      .filter(child => child !== null && child !== false)
      .map(child => child instanceof Object ? child : createTextElement(child));

    return { type, props };
  }

  function createTextElement(value) {
  return {
    type: TEXT_ELEMENT,
    props: {
      nodeValue: value
    }
  };
}
  
  return {createElement: createElement, render: render}
}
              
            
!
999px

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