AList - Eloquent Javascript, Chapter 4 - https://repl.it/@Luke_Rogerson/AList

AList.js

/*
let list = {
  value: 1,
  rest: {
    value: 2,
    rest: {
      value: 3,
      rest: null
    }
  }
};
*/

/* Write a function arrayToList that builds up a list structure like the one shown when given [1, 2, 3] as argument. Also write a listToArray function that produces an array from a list. Then add a helper function prepend, which takes an element and a list and creates a new list that adds the element to the front of the input list, and nth, which takes a list and a number and returns the element at the given position in the list (with zero referring to the first element) or undefined when there is no such element. */

function arraytoList () {

  const array = [1,2,3];
  let list;

  for (let x = array.length-1; x >= 0; x--) {
    list = {value: array[x], rest:list};
  }

return list;

}


function listToArray(list) {
  let newArray = [];
  for (let node = list; node; node = node.rest) {
    newArray.push(list.value);
    list = list.rest;
  }
  return newArray;
}

function helper () {
  for (let node = lits; node; node= node.rest) {

  }
}

listToArray(arraytoList());

// Still need to implement prepend and nth functions.