design_pattern5.js

const wordCountElement = document.createElement('p');

wordCountElement.className = 'wordCount';
wordCountElement.innerHTML = 'Word Count: <strong id="blogWordCount">0</strong>';
document.body.appendChild(wordCountElement);

const blogObserver = new EventObserver();

blogObserver.subscribe((text) => {
  const blogCount = document.getElementById('blogWordCount');

  blogCount.textContent = getWordCount(text);
});

const blogPost = document.getElementById('blogPost');

blogPost.addEventListener('keyup', () => blogObserver.broadcast(blogPost.value));