Object.prototype.extends = function (properties) {
    function f() { }    ;
    var prop;
    f.prototype = Object.create(this);
    for (prop in properties) {
        f.prototype[prop] = properties[prop];
    };
    f.prototype._super = this;
    return new f();
}

var Prototypal = (function() {
    var shape = {
        init: function(x, y, color) {
            this._x = x;
            this._y = y;
            this._color = color;
            return this;
        },
        toString: function() {
            return 'X: ' + this._x + ', Y: ' + this._y;
        }
    }

    var circle = shape.extends({
        init: function(x, y, color, r) {
            this._super.init.call(this, x, y, color);
            this._r = r;
            return this;
        },
        toString: function() {
            return this._super.toString.call(this) + ', R: ' + this._r;
        }
    });

    var rect = shape.extends({
        init: function(x, y, width, height, color) {
            this._super.init.call(this, x, y, color);
            this._width = width;
            this._height = height;
            return this;
        },
        toString: function() {
            return this._super.toString.call(this) + ', Width: ' + this._width + ', Height: ' + this._height;
        }
    });

    var triangle = shape.extends({
        init: function(x, y, x1, y1, x2, y2, color) {
            this._super.init.call(this, x, y, color);
            this._x1 = x1;
            this._y1 = y1;
            this._x2 = x2;
            this._y2 = y2;
            return this;
        },
        toString: function() {
            return this._super.toString.call(this) + ', X1: ' + this._x1 + ', Y1: ' + this._y1 +
                ', X2: ' + this._x2 + ', Y2: ' + this._y2;
        }
    });

    var line = shape.extends({
        init: function(x, y, x1, y1, color) {
            this._super.init.call(this, x, y, color);
            this._x1 = x1;
            this._y1 = y1;
            return this;
        },
        toString: function() {
            return this._super.toString.call(this) + ', X1: ' + this._x1 + ', Y1: ' + this._y1;
        }
    });

    var segment = shape.extends({
        init: function(x, y, x1, y1, color) {
            this._super.init.call(this, x, y, color);
            this._x1 = x1;
            this._y1 = y1;
            return this;
        },
        toString: function() {
            return this._super.toString.call(this) + ', X1: ' + this._x1 + ', Y1: ' + this._y1;
        }
    });

    return {
        Shape: shape,
        Circle: circle,
        Rect: rect,
        Triangle: triangle,
        Line: line,
        Segment: segment
    }
}());

var shape = Object.create(Prototypal.Shape).init(1, 2, "660066");
console.log(shape.toString());

var circle = Object.create(Prototypal.Circle).init(1, 2, "662266", 5);
console.log(circle.toString());

var rect = Object.create(Prototypal.Rect).init(1, 2, 4, 4, "662266");
console.log(rect.toString());

var triangle = Object.create(Prototypal.Triangle).init(1, 2, 4, 4, 5, 5, "662266");
console.log(triangle.toString());

var line = Object.create(Prototypal.Line).init(1, 2, 4, 4, "662266");
console.log(line.toString());

var segment = Object.create(Prototypal.Segment).init(4, 4, 2, 2, "662266");
console.log(segment.toString());