dont-do-this.js

function highlyExpensiveFunction(elementNode) {
  $(elementNode).css({
    'position': 'fixed'
  });

  offsetTop = $(elementNode).offset().top;
  offsetLeft = $(elementNode).offset().left;
  anotherExpensiveFunction(elementNode, offsetTop, offsetLeft);
  return elementNode;
}


// Let’s finish setting up this short example by calling this with some setup code.
function initExpensiveWork(elementNode) {
  $(elementNode).on('scroll', function () {
    highlyExpensiveFunction(elementNode);
  });
}