JSFiddle - React, Tailwind, and code Playground

HTML

<body>
    
</body>

JavaScript

var _privAlien =  {
    x:null
};

var alien = {
    get x(){
        return function(x){
            if(!x)
                return _privAlien.x;
            else
            _privAlien.x = x;
        };
    },
    set x($var){
        this.x($var);
    }
};

alien.x(293);
//or
alien.x = 293;  

window.document.writeln(alien.x()); // == "293"