I have read that creating a namespace for JavaScript projects helps to reduce conflicts with other libraries. I have some code with a lot of different types of objects for which I have defined constructor functions. Is it good practice to put these inside the namespace as well?

For example:

var shapes = {
    Rectangle: function(w, h) {
        this.width = w;
        this.height = h;
    }
};

which can be called via:

var square = new shapes.Rectangle(10,10);