Clear the element

Create a function clear(elem) that removes everything from the element.

<ol id="elem">
  <li>Hello</li>
  <li>World</li>
</ol>

<script>
  function clear(elem) { /* your code */ }

  clear(elem); // clears the list
</script>

First, let’s see how not to do it:

          function clear(elem) {
  for (let i=0; i < elem.childNodes.length; i++) {
      elem.childNodes[i].remove();
  }
}
        

That won’t work, because the call to remove() shifts the collection elem.childNodes, so elements start from the index 0 every time. But i increases, and some elements will be skipped.

The for..of loop also does the same.

The right variant could be:

          function clear(elem) {
  while (elem.firstChild) {
    elem.firstChild.remove();
  }
}
        

And also there’s a simpler way to do the same:

          function clear(elem) {
  elem.innerHTML = '';
}
        