So the -> thing de-references things? No... for Game Maker, it should just be the dot. We don't want to de-reference anything, therefore we don't want ->. For example:inst = instance_create(x, y, object); dist = inst.point_distance(x, y, 32, 32);We don't want to derefrence the variable that has the instance ID, therefore it would seem to me the dot is more appropriate. Instance.method() is pretty much a "normal reference". So yeah, there's no reason to complicate things with a dot vs ->. This is Game Maker, just keep it simple.
Actually - you ARE dereferencing inst. What value does inst contain? It contains a # which represents the new instances position in memory. It is thus functioning as a pointer. A further testament to this is the fact that you can change the value contained in inst and thus point to different instances in memory.