JSFiddle - React, Tailwind, and code Playground

JavaScript

function myStore() {
  items = [];

  this.add = function(item) {
    items.push(item);
  };

  this.all = function() {
    return items;
  };
}

let store = new myStore;

console.log(store.all());

store.add('test');

console.log(store.all());