Discussion on: Performance: Create a new variable or reassign the value?

[deexter]

Could you provide some example? I am not sure what do you mean

[Fernando Marques]

Hello!
For example, in order to assign a property to a CSS element via Javascript:

  let all = document.getElementsByClassName('class1');
  for (let i = 0; i < all.length; i++) {
    all[i].style.transitionDuration = time + 's';
  }
// reassign previous variable
  all = document.getElementsByClassName('class2');
  for (let i = 0; i < all.length; i++) {
    all[i].style.transitionDuration = time + 's';
  }
// OR
// create another variable
  let all_2 = document.getElementsByClassName('class3'); 
  for (let i = 0; i < all_2.length; i++) {
    all_2[i].style.transitionDuration = time + 's';
  }

Is the difference even relevant?

[deexter]

I think performance meant in time spent to do this operation will be same, but memory consumption will be higher in last example.