Exactly, where to draw a line? Explaining a concept of abstract and virtual machines may take a few pages of a dense text, explaining how to parse expressions w

Exactly, where to draw a line? Explaining a concept of abstract and virtual machines may take a few pages of a dense text, explaining how to parse expressions with precedence may require dozens of pages, explaining C types will add a few more. So, yes, it's either you're curious enough to dig into a code and find the relevant explanations somewhere else (the said Dragon Book and alike), or you won't get it, regardless of how comprehensive comments are.