Uncaught reference error

[dojob]

I got Uncaught ReferenceError: Point is not defined for the following code. Anyone know what is the reason. I am suspecting that this is due to the fact that it does not have the function Point(). But the book also does not provide function Point() in this example.

Reference book

function setupCurrentLevel(){
untangleGame.circles = [];
var level = untangleGame.levels[untangleGame.currentLevel];
for(var i = 0; i < level.circles.length; i++){
untangleGame.circles.push(new Point(level.circles[i].x, level.circles[i].y, 10));
}

// setup line data after setup the circles
connectCircles();
updateLineIntersection();
}

[Old Pedant]

Correct.

But it looks like that chapter is building on the work in prior chapters, and I'll bet that Point is defined in one of the prior chapters.