LeetCode: linked-list-based stack, more performant than default JS's array-based one

simple-js-stack.js

function createStack() {
  const empty = { next: undefined, value: undefined! };
  let top = empty;
  function isEmpty() { return top === empty; }
  function push(v) { top = { next: top, value: v }; }
  function pop() {
      if (!top.next) throw new Error('Can not pop from empty');
      const { value } = top;
      top = top.next;
      return value;
  }
  function peek() { return top.value; }
  function clear() { top = empty; }
  return { isEmpty, push, pop, peek, clear };
};


// ts
function createStack<T>() {
  const empty: Elem<T> = { next: undefined, value: undefined! };
  let top: Elem<T> = empty;
  function isEmpty(): boolean { return top === empty; }
  function push(v: T) { top = { next: top, value: v }; }
  function pop(): T {
      if (!top.next) throw new Error('Can not pop from empty');
      const { value } = top;
      top = top.next;
      return value;
  }
  function peek(): T { return top.value; }
  function clear(): void { top = empty; }
  return { isEmpty, push, pop, peek, clear };
};

interface Elem<T> {
  next?: Elem<T>;
  value: T;
}