Why didnt you scan this using an FSM?

[lewibs]

craftinginterpreters/java/com/craftinginterpreters/lox/Scanner.java

Line 59 in 4a840f7

private void scanToken() {

[HallofFamer]

Because it is not necessary? Lox’s syntax is simple enough that a handwritten lexer does the work easily. Also Crafting Interpreters is not a book that teaches you algorithms, nor does it require that you understand them before reading this book. It is designed to be accessible to a wide range of audience, even those without CS background, especially the first part of the book written in Java for a Treewalk interpreter.