Writing OOP using OOP

As many people have pointed out, if you turn your head sideways and squint, the following JavaScript can be considered a “class:” function QuadTree (nw, ne, se, sw) { this._nw = nw; this._ne = ne; this._se = se; this._sw = sw; } QuadTree.prototype.population = function () { return this._nw.population() + this._ne.population() + this._se.population() + this._sw.population(); } This is very differen