I'm sure that I don't need to tell you that there are many things in this world that look easy, but are in fact very hard. Even things that are very simple at t

I'm sure that I don't need to tell you that there are many things in this world that look easy, but are in fact very hard. Even things that are very simple at the core turn out to be very difficult in practice. I mean, to be a little flippant, all you need is abstraction and application, and you can compute all computable problems, right? More to the point: what I was trying to do was to point out the irony of saying "building a garbage collector is easy" and then, only a few sentences later, saying "this code may have subtle bugs." Saying "this code is not fast enough for production" would be one thing, saying "this code is not correct" seems to put lie to the assertion that building it is "easy." I personally have never built a garbage collector in anger. But I suspect that the problem of building a passable garbage collector (that is, one that somebody else would be willing to use) is quite a bit harder than it is made out to be in this article.