Closure

const secureBooking = function () {
  let passengerCount = 0;
  return function () {
    passengerCount++;
    console.log(`${passengerCount} passengers`);
  };
};
const booker = secureBooking();
booker();
booker();
booker();
console.dir(booker);
///////////////////////////////////////
// More Closure Examples
// Example 1
let f;
const g = function () {
  const a = 23;
  f = function () {
    console.log(a * 2);
  };
};
const h = function () {
  const b = 777;
  f = function () {
    console.log(b * 2);
  };
};
g();
f();
console.dir(f);
// Re-assigning f function
h();
f();
console.dir(f);
// Example 2
const boardPassengers = function (n, wait) {
  const perGroup = n / 3;
  setTimeout(function () {
    console.log(`We are now boarding all ${n} passengers`);
    console.log(`There are 3 groups, each with ${perGroup} passengers`);
  }, wait * 1000);
  console.log(`Will start boarding in ${wait} seconds`);
};
const perGroup = 1000;
boardPassengers(180, 3);