Element#index and Element#indexOfType

[jwestbrook]

previous lighthouse ticket #1357
by Michael Morris

---

I find myself needing to figure out an element's ordering among its siblings often enough to consider a universal method for it. Consider the following DOM

<ul>
  <li id="first">Apple</li>
  <li id="second">Orange</li>
  <li id="third">Pear</li>
</ul>

The command $('first').index() would return 0, that element's position among its siblings. However, this function wouldn't consider tag types by design. Faced with a mixed tag type collection it still returns the index, but if the user wants nth-of-type they would have to use the proposed sibling function indexOfType.

<div>
  <div id="first">Hello there</div>
  <section id="second"> Sectioning</section>
  <article id="third"> articles</article>
  <div id="fourth"> and so on.</div>
</div>

With the DOM above $('fourth').index() returns "3". $('fourth').indexOfType() returns "1" since it is the second div tag in the group.

Thoughts?