I can’t say that I really like the railroad diagrams for describing the syntax of the language as much as I’d like more example code. I suppose the diagrams are more inclusive, they just seem a little excessive for what information they provide.
Yes, this is an incredibly terse book. Some rather hefty topics are given a few lines of discussion. Not that this is terrible, but it makes for a slow read. He establishes a few helper functions & methods to allow you to do certain tasks a lot easier, such as easier object creation and inheritance. These functions are referred to later on in the book as if they were parts of the core language, so you really need to know both the book and the core language very well.