Code example from blogpost https://medium.com/variant-as/abstracting-the-dom-by-making-ad-hoc-react-like-library-1c9b42618e63

own-ui-21.js

const { button } = createUiFramework();
let initialState = { counter: 0 };

// Our application taking a state.
function app(state) {
  // When we click on the button, rerender with new state where the counter is incremented
  const onClick = () => render(app, { ...state, counter: state.counter + 1 });
  return button({ type: "button", onClick }, `Increment ${state.counter}!`);
}

// Render function similar to React.
function render(fn, s) {
  // Empty body, just to illustrate a point. Shouldn't be used in production.
  document.body.innerHTML = "";
  
  // Re-add our components with state.
  document.body.appendChild(fn(s));
}

// Do initial render
render(app, initialState);