Javascript Array ES6 Undefined Error

Question

I'm having trouble solving this question (the result is always undefined) and I am not sure what I'm doing wrong... any ideas?

Write a function that takes a number and generates a list from 0 to that number.

Use the function to assign a value to the myNumberList variable so that it has the value of a list going from 0 to 5.

Assign a value to the variable secondLastItem that should be the second last item of the myNumberList array.

function listMaker(listLength) {}

var myNumberList = null; // replace with number list created by listmaker

var secondLastItem = null; // replace with second last item

Answer 1

You can try the following way using ES6 's spread operator ( ... ):

 function listMaker(listLength) { return [...Array(listLength).keys()]; } var myNumberList = listMaker(10); // If you want the specified number passed as argument to be included as the last item in the array then push it. myNumberList.push(10); console.log(myNumberList); 

Answer 2

Here is one way to write it:

  function listMaker(number) { var secondToLast; var list = []; for (var i = 0; i <= number; i++){ list.push(i); } secondToLast = list[list.length - 2]; return [list, secondToLast] } var list = listMaker(5)[0]; var secondToLast = listMaker(5)[1] console.log(list + "\\n" + secondToLast); 

That is the snippet ^

Here is the jsfiddle