Real life ES6 examples

es6-examples.js

const lastPickupDate = items => items
  .filter(i => i.returnQuantity)
  .map(i => i.pickupDate)
  .sort((a, b) => +new Date(b) - +new Date(a))
  .find(i => i);

const orderTotal = order => {
  const totalNormalItems = order.items
      .filter(x => !x.shipping)
      .reduce((prev, cur) => prev + cur.quantity * cur.price, 0)
  const shippingItem = order.items.find(x => !!x.shipping)
  const shipping = totalNormalItems > 1000 ? 0 : shippingItem.price
  return totalNormalItems + shipping
}

const removeDuplicates = arr => [... new Set(arr)];

const sleep = ms => (new Promise(resolve => setTimeout(resolve, ms)));