const o = {};

o.constructor === Object;

/* A constructor in Javascript is used to create a new object and set values

for any existing object properties*/

​

class Animal{

  constructor (name, height, weight){

    console.log("created animal named", name)

  }

  nameLength() {

    return name.length;

  }

}

 var dog = new Animal("Fido", 25, 90);

 var fish = new Animal("Goldie", 2, .02);

​

    console.log(dog.nameLength);

​

//Constructor Function

function BellBoy (name, age, hasWorkPermit, languages) {

  this.name = name;

  this.age = age;

  this.hasWorkPermit = hasWorkPermit;

  this.languages = languages;

}

​

//Create New Object From Constructor Using Arguments

var Earl = new BellBoy('Earl E.Bird', 23, true, ['French', 'German'])

​

//Access the Properties and Their Values

console.log('Name : ', Earl.name)

console.log('Age : ', Earl.age)

console.log('Verified Work Permit : ', Earl.hasWorkPermit)

console.log('Languages : ', Earl.languages)

var MyConstructor = function(p1, p2, p3){

  this.p1 = p1;

  this.p2 = p2;

  this.p3 = p3;

};

//Constructor function is  function that generate object.

//capital function name indicate it is constructor function

function Todo(name, completed) {

  console.log(this); //return empty object name todo

  this.name = name;

  this.completed = completed;

  this.getTodoName = function () {

    console.log(this.name);

  };

}

//new keyword do two things

//create new empty object

//and assign this with that object.

const todo = new Todo('Get Eggs', false);

console.log(todo); //log return object

todo.getTodoName(); //logo Get Eggs

​