DEV Community


A simple interview question

jrock2004 profile image John Costanzo ・1 min read

I went on an interview and I was asked a question like the one in the codepen. I was asked to fix it as its broken. Just curious how others would answer this one

Here it is on CodePen

Discussion (4)

Editor guide
isaacdlyman profile image
Isaac Lyman


if ($element.filter('.js-cool, .js-beans')) {


if ($element.filter('.js-cool, .js-beans').length) {

.filter returns an Array, which inherits from Object, and all Objects are truthy in JavaScript.

jrock2004 profile image
John Costanzo Author

That is a good way to solve this

arsho profile image
Ahmedur Rahman Shovon

We can use a check to see what values the input has at keyboard events. Then if it has empty string we can simply restore the original font-size of the mentioned classes.

Here is an approach to do so:

$(function() {
  $(".checker").on("keydown keyup", function(ev) {
    $(".js-cool, .js-beans").css("font-size", "24px");
    $input_val = $(this).val();
    if ($input_val == "") {
      $(".js-cool, .js-beans").css("font-size", "inherit");
malines profile image
Birger Hoornaert

Why looping over all objects and filter out then when you can start with a beter filter.

$('.js-cool, .js-beans').each(function() {
    $(this).css("font-size", "24px");