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JavaScript

Posted by Zach Handler
.a{fill-rule:evenodd;}techdegree
Zach Handler
Web Development Techdegree Student 5,332 Points

.pop

When typing this array in the console :

var nums = [1, 2, 3, 4, 5, 6];

and you type nums.pop();

you get a return value of 6. But since the length of the array is now 5, shouldn't it say 5?

For example, when you do nums.push(7); it returns the number 7 (because there are now 7 items in the array).

What's the difference?

2 Answers

Steven Parker
Steven Parker
229,708 Points
Steven Parker
Steven Parker
229,708 Points

The return value of a "pop" is not the number of items left in the array — it's the value of the item that it removes from the array. So in this example, it removes the value "6" from the end of the list.

On the other hand, "push" does return the number of items in the array.

Blake Larson
Blake Larson
13,014 Points
Blake Larson
Blake Larson
13,014 Points

Pop() removes the last index of an array and returns the removed item. If it was [1,2,3,4,5,9] it would return 9 and nums is now [1,2,3,4,5].

If you do it to nums again like: let lastNum = nums.pop();

console.log(lastNum); 5 console.log(nums.length); 4