Constant expressions in C++ are not as constant as you might think. For example, the following program will cause a compiler error.

// example0.cpp
#include "borrow.hpp"

int
main() {
  using…

There are many good OpenGL tutorials out there. They have good explanation on how OpenGL works. However, most of them treat OpenGL as a black box. It would be better to implement a small part of OpenGL to see how things fit together.

To deal with circular references, a garbage collector has to keep track of all references between garbage collected objects. Typically, for statically typed language, a list of offsets to all references to other garbage…