Script to sort HN links by comments count

hn_sorter.js

/** Script to sort HN comments by post date **/

var itemsArray = [],
    tb = document.querySelectorAll('table.itemlist > tbody > tr');

function sortBycom(a, b) {
  var left = a[1].querySelector('td.subtext > a:last-child'),
      right = b[1].querySelector('td.subtext > a:last-child');

  // If no comments has been made yet, push them at the end
  if (left.innerText === "discuss") { 
    return 1;
  } else if (right.innerText === "discuss") {
    return -1;
  }

  left = parseInt(left.innerText.split(' ')[0], 10);
  right = parseInt(right.innerText.split(' ')[0], 10);
      
  return right - left;
};

// Each HN "item" consists of 3 rows : tr.athing - tr - tr.spacer.
// Let's collect them 3 by 3. 

for (var i = 0; i < 90; i+= 3) {
  itemsArray.push(Array.prototype.slice.call(tb, i, i + 3)) 
}

itemsArray.sort(sortBycom);

// Remove tbody children to make space for the sorted one.
tb.forEach( e => {
    var parent = e.parentNode;
    parent.removeChild(e);
});

// Add the list (not looking for performance here)
itemsArray.forEach( e => {
    var parent = document.querySelector('table.itemlist > tbody');
    e.forEach( r => { parent.appendChild(r) });
});