从console.log隐藏时在__proto__上定义函数

Question

Can I define functions on proto? Part of the objective is to have getter and setters but not creating any noise when I console.log the object. I've noticed anything defined on prototype is not included in the console.log .

function ValueObject() {
    var authentication; //private variable

    __proto__.getAuthentication = function() {return authentication};
    __proto__.setAuthentication = function(val) {authentication = val};

    this.val = val;
}

Desired behavior.

var vo1 = new ValueObject(1);
console.log(vo1); // ValueObject { val: 1 } (desired behavior)

My objective is to show value only in console.log while hiding all those getters and setters from user of the library because they are of internal nature and use.

The problem is getter and setters are not accessible when i instantiate the object.

Answer 1

function ValueObject(val) {

    private_val = val; //private

    ValueObject.prototype.get =()=> {
        this.authentication = private_val;

        return this.authentication; // public now
    }
}
var auth = new ValueObject('test');
alert('private: '+auth.private_val); // can't receive, it's private hence undefined
alert('private: '+auth.authentication); // neither
alert('public: '+auth.get()); // here you can

IMHO, that's the basic principal. should be working - and ()=> is short for function() .

EDIT: and here for a set/get construct example... this should work too:

function ValueObject() {

    var private_val; //private

    ValueObject.prototype.set =(val)=> {
        private_val = val; // private variable gets a value 
    }

    ValueObject.prototype.get =()=> {
        this.authentication = private_val; // public variable gets the private value 

        return this.authentication; // public now
    }
}
var auth = new ValueObject;
auth.set('test');
alert('private: '+auth.private_val); // can't receive, it's private hence undefined
alert('private: '+auth.authentication); // neither
alert('public: '+auth.get()); // here you can

check demo

Answer 2

The private variable needs to be publicly exposed in order to access it from the prototype chain. If you need the variable to be private, you will have to deal with seeing the public functions in the console.