checkCoupons.js

// Story
// Your online store likes to give out coupons for special occasions. Some customers try to cheat the system by entering invalid codes or using expired coupons.

// Task
// Your mission:
// Write a function called checkCoupon which verifies that a coupon code is valid and not expired.

// A coupon is no more valid on the day AFTER the expiration date. All dates will be passed as strings in this format: "MONTH DATE, YEAR".

// Examples:
// checkCoupon("123", "123", "July 9, 2015", "July 9, 2015")  ===  true
// checkCoupon("123", "123", "July 9, 2015", "July 2, 2015")  ===  false
function checkCoupon(enteredCode, correctCode, currentDate, expirationDate){
    return enteredCode===correctCode && new Date(currentDate) <= new Date(expirationDate);
  }