Can I define custom operator overloads in Javascript? [duplicate]

Answer 1

You can change built-in methods of objects in JavaScript, such as valueOf() method. For any two objects to apply the following operators >, <, <=, >=, -, + JavaScript takes the property valueOf() of each object, so it deals with operators kind of like this: obj1.valueOf() == obj2.valueOf() (this does behind the scenes). You can overwrite the valueOf() method depends on your needs. So for example:

var Person = function(age, name){
    this.age = age;
    this.name = name;
} 

Person.prototype.valueOf(){
    return this.age;
}

var p1 = new Person(20, "Bob"), 
    p2 = new Person(30, "Bony");

console.log(p1 > p2); //false
console.log(p1 < p2); //true
console.log(p2 - p1); //10
console.log(p2 + p1); //40

//for == you should the following
console.log(p2 >= p1 && p2 <= p1); // false

So this is not the precise answer for your question, but I think this can be an useful stuff for that kind of issues.