Suggestion for how JS class syntax should be

Point-concise.js

class Point {

    public x, y;

    Point(x, y)
    {
        this.x = x; 
        this.y = y;
    }

    public equals(point) { return x === point.x && y === point.y);

    public length( return Math.sqrt(x * x + y * y);

}

Point.js

/**
 *  Class Doc
 */
class Point {


    //----------------------------------
    //  Private Members 
    //----------------------------------

    private var _x;

    private var _y;

    //----------------------------------
    //  Constructor 
    //----------------------------------

    /**
     *  Constructor Doc
     */
    Point(x, y)
    {
        //since function variables have the same name as class members
        // use 'this' to refer to class variables
        this._x = x; 
        this._y = y;
    }

  
     

    //----------------------------------
    //  Methods 
    //----------------------------------

    private function myPrivateMethod()
    {
       //private method
    }


    public function toString()
    {
        return "["+x+", "+y+"]";
    }



    public function get x()
    {
        return _x; //Scope includes class variables
    }

    // Having the ability to define a setter for a private member
    // helps reduce errors by checking the value before setting
    // (as opposed to just having `public var x`).
    // Setters and getters are not necessary, however;
    // public var x, y;    

    public function set x(value)
    {
        if(!value)
            throw "Set y error"; //or whatever you want to do with it.
        _x = value;
    }

    public function get y()
    {
        return _y;
    }

    public function set y(value)
    {
        if(!value)
            throw "Set y error";
        return _y;
    }

   

}