What are the advantages / disadvantages of creating functional objects in JavaScript?

Question

I just watched Douglas Crockford talk about how prototypical inheritance is "also bad"

YouTube 35m55s

I am not interested in his views on prototype inheritance combined with JavaScript, since it is such an important part of the language that it will always be there.

But I would like to know what benefits I get using the creation of the functional object that it shows in the link:

// Class Free Object Oriented Programming
function constructior(init) {
    var that = other_constructor(init),
        member,
        method = function () {
            // init, member, method
        };
    that.method = method;
    return that;
}

After the video, I will re-read the part about creating a functional object in his book "Good JavaScript Details" Chapter 5: Inheritance.

But I can’t see the big difference . I can get private members just fine with the constructor template:

function Constructor (value) {
    var private = value;
    this.getPrivate = function () {
        return private;
    }
}
var OBJ1 = new Constructor(5);
var OBJ2 = new Constructor('bacon');

console.log( OBJ1.getPrivate() ); // 5
console.log( OBJ2.getPrivate() ); // bacon

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:

var panda = createBear();

:

var panda = new Bear();

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Answer 1

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TL; DR:

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new , , "use strict"; , , new.

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---

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var Constructor = function () {
    this.x = 0;
    this.y = 0;
};
var A = new Constructor();
console.log(A instanceof Constructor ); // true

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:

Constructor.prototype.color = 'yellow';

, Constructor, .color, .

var A = new Constructor();
console.log(A.color); // yellow
console.log(A.hasOwnProperty('color')); // false

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var A = new Constructor();
Constructor.prototype.food = 'bacon';
console.log(A.food); // bacon;

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Constructor.prototype.number = 5;
A.calculate = function () {
    return A.number * 5;
}
console.log(A.calculate()); // 25

Constructor.prototype.number = 'fishsticks';
console.log(A.calculate()); // NaN

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. .__proto__. Object.getPrototypeOf().

console.log(Object.getPrototypeOf(A.color)); // yellow

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var A = Constructor();
console.log(A); // undefined

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var Constructor = function () {
    "use strict";
    this.x = 0;
    this.y = 0;
}
var A = Constructor();

console.log(A);
// Uncaught TypeError: Cannot set property 'x' of undefined

Factory

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function factory () {
    var obj = {
        x: 0,
        y: 0
    }
    return obj;
}
var A = factory(); // {x: 0, y: 0}

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function factory () {
    if ( new Date().getHours() < 8 ) { 
        return "can't create object. Need Coffe!" 
    };
    var obj = {
        x: 0,
        y: 0
    }
    return obj;
}
var A = factory(); // Before 8 am: "can't create object. Need Coffe!"
var A = factory(); // After 8 am: {x: 0, y: 0};

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factory.prototype.foo = "bar";
A = factory();
console.log(A.foo); // undefined

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. TL; DR

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:

JavaScript , , ?

vs Factory

JavaScript