Discussion on: Learn basic Web Components

[Zsolt Gulyas]

Truly said. Altough I wouldn't say just because of this, that the docs are "incorrect". Maybe the first one is more readable for newcomers. Anyway, super useful comment though. Thanks.

[Danny Engelman]

See what code newcomers have to dig through (unless they don't RTFM) in the attachShadow MDN documentation: developer.mozilla.org/en-US/docs/W...

If you understand "// Always call super first in constructor" is incorrect
you can write that 33 lines constructor (most likely) without any comments:

constructor() {

  let span = document.createElement('span');

  function countWords() {
    let node = this.parentNode;
    let text = node.innerText || node.textContent;
    let count = text.trim().split(/\s+/g).length;
    span.innerText = 'Words: ' + count;
  }

  super()
   .attachShadow({mode: 'open'})
   .append( span );

  countWords();
  setInterval(()=> countWords() , 200);
}

If you want to score W3C points; feel free to update that MDN article.

I did some MDN updates; then concluded there is way more effect adding comments to Web Component blogposts.
And I recently published my first Dev.to post explaining Web Components are about semantic HTML (IMHO)

And ... there is more wrong in that MDN Count Words example..

• this.parentNode DOM access should be done in the connectedCallback, as the DOM might not even exist when the constructor runs

• <p is="word-count"></p> Will never work in Safari, because Apple only implemented Autonomous Elements and (for the past 5 years) has strong arguments to not implement Customized Built-In Elements