JavaScript Closure with Properties and Variables. In this example you can see that work with closure you can define properties or variables after use it.

closure-with-properties-and-variables.js

/**
 * Title: JavaScript Closure with Properties and Variables.
 *
 * Description: In this example you can see that work with closure you can define
 *              properties or variables after use it.
 * 
 * More Info: https://developer.mozilla.org/es/docs/Web/JavaScript/Closures
 */

// Define Anonymous Function for encapsulate from Root Scope.
(function () {

  // Create Main Closure Function.
  function vehicle() {

    // Set default properties and values.
    this.statusDoors = 'close';

    // Contructor for return all instance.
    function constructor () {
      return this;
    }

    // Toggle and Get Status Door Methods.
    this.toggleStatusDoors = function () {
      return this.statusDoors === 'close' ? this.statusDoors = 'open' : this.statusDoors = 'close';
    }
    this.getStatusDoors = function () {
      return this.statusDoors;
    }

    // Set and Get Color Methods.
    this.setColor = function (value) {
      return value ? color = value : 'Color value is required.';
    }
    this.getColor = function () {
      return color;
    }
    // Set default variables and values.
    let color = 'black';

    // Return all Closure Object.
    return constructor;
  }

  // Define Vehicle (A) with Vehicle Object.
  const vehicleA = vehicle()();

  // Get Status Door and Color.
  console.log(vehicleA.getStatusDoors());
  console.log(vehicleA.getColor());

  // To check that you can´t set color without value.
  console.log(vehicleA.setColor());

  // Toggle and Get Status Doors method.
  console.log(vehicleA.toggleStatusDoors());
  console.log(vehicleA.getStatusDoors());

  // Set and Get New Color Value.
  console.log(vehicleA.setColor('white'));
  console.log(vehicleA.getColor());

  /**
   * If you log vehicleA object you can see that you hace all properties and method less the variable color.
   */
  // console.log(vehicleA);
})();

/**
 * If you log vehicleA object return that is not defined, this is normal you are in different scope.
 * The scope goes from the inside out and not the opposite.
 */
// console.log(vehicleA);