jsPointPrototypeBased

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Study</title>
</head>
<body>
    <div id="output"></div>
    <script>
        'use strict'

        {
            function Point(pX, pY) {
                this.x = pX;
                this.y = pY;

                Point.prototype.print = function () { console.log(`(${this.x},${this.y})`); }
                Point.prototype.getX = function () { return this.x; };
                Point.prototype.getY = function () { return this.y; };
                Point.prototype.setX = function (pX) {
                    if (pX >= 0) {
                        this.x = pX;
                        return true;
                    };
                    return false;
                }
                Point.prototype.setY = function (pY) {
                    if (pY >= 0) {
                        this.y = pY;
                        return true;
                    };
                    return false;
                }
            }

            let p1 = new Point(21, 22);
            /// p1.x = -123545;
            let p2 = new Point(211, 212);
            Point.prototype.move = function (dX, dY) { this.x += dX; this.y += dY; }
            let p3 = new Point(26, 7);

            p1.print();
            p1.setX(42);
            p2.print();
            p2.setY(33);

            p1.print();
            p2.print();
            p3.print();

            p2.move(5, 6);
            p2.print();
            p3.move(5, 6);
            p3.print();

            console.log(p1);
            console.log(p2);
            console.log(p3);
            console.log(p1.__proto__ == Point.prototype);
            console.log(p3.__proto__ == Point.prototype);
            console.log(p3.__proto__ == p1.__proto__);
        }
    </script>
    <h1></h1>
</body>
</html>