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stevefan1999
Really I would love to know how parse context sensitive stuff like typedef which will have "switched" syntax for some tokens. Would like to know things like "hoisting" in C++, where you can you the class and struct after the code inside the function too, but I just find it hard to describe them in rigorous formal language and grammar.

Hacky solution for PEG such as adding a context stack requires careful management of the entry/exit point, but the more fundamental problem is that you still can't "switch" syntax, or you have to add all possible syntax combination depending on the numbers of such stacks. I believe persistent data structure and transactional data structure would help but I just couldn't find a formalism for that.

torginus
C/C++ has one of the worst-designed syntaxes, its such a shame that entire families of the most popular languages ended up copying the same mistakes.

I know it's no solace to you, but Rust and Go don't even have this problem Afaik, and it's avoidable by careful consideration.

suspended_state
I don't really know what you mean by "worst-designed syntax". Do you mean that the design process was bad, or that the result is bad?
Nora23
One of the best resources for learning compiler design. The web version being free is incredibly generous.
fuzztester
Compiler doesn't match the title of the book.
fuzztester
Ignorant HN downvoting monkeyboys at it again. Caint call em men, hee hee, ho ho.
chrysoprace
I've found this book to be a good way to learn a new language, because it forces you to do a bit of reading about various language features and patterns to create equivalent implementations. For languages that lack some of the features in Java, it can be tricky to learn how to apply similar patterns, but that's half the fun (for me).
acedTrex
I have bought the print version of this 3 seperate times to give as a gift, its excellent.
munificent
Thank you for buying copies! :D
acedTrex
Thank you for writing an awesome book!
keyle
It's a great book, I bought the paper version first, but man it was too big and heavy for my liking, ended up buying a digital copy; much more practical for notes and search...

although I keep getting lost somewhere in the mountain :)

I also recommend munificent's other book about game programming patterns. Both are fun to read.

flir
Sometimes I get the spine guillotined off and replaced with a ring binding. Any print shop can do it for you, and you just lose the gutter plus a little margin. Easier to work with at a desk, and you can even split into two "books" if you feel it necessary.

But that's only for books I don't want to keep, and Crafting Interpreters is definitely a keeper...

raymond_goo
Crafting Interpreters is the one thing that LLM's can do really really well. Because it is so easy to define and test.

Here are is a new LUA interpreter implemented in Python:

https://github.com/rhulha/MoonPie

And here is a new language:

https://github.com/rhulha/EasyScript

ramon156
What even is the point of that? The whole point of the book is to get a sense and mindset of crafting compilers.
HarHarVeryFunny
Is MoonPie your project? Have you written up anything about your experience and process of creating it?
wiseowise
LLMs can write much better comments than you do, but for some reason you continue to write them. Why?
jokoon
I stopped reading when he started using the visitor pattern
volemo
What’s bad about the visitor pattern? /gen
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ceronman
The visitor pattern is very common in programming language implementations. I've seen it in the Rust compiler, in the Java Compiler, in the Go compiler and in the Roslyn C# compiler. Also used extensively in JetBrains' IDEs.

What do you have against this pattern? Or what is a better alternative?

goodthink
Reading this book brought me a better understanding of "the expression problem" and the use of the visitor pattern as its solution. This led me to (finally) grok the use of Class _Heirarchy_ Inheritance[0] as a solution not requiring visitors. In Newspeak[1], classes can contain nested classes, so when you subclass a class, you inherit the nested classes as well. This blog post discusses the same feature affording Free Object Algebras [2].

[0] https://blog.bracha.org/primordialsoup.html?snapshot=Amplefo... [1]https://newspeaklanguage.org [2]https://blog.bracha.org/primordialsoup.html?snapshot=Amplefo...

papercrane
I love this book! I do wish there was a new edition that updated the version of Java used in the tree-walk interpreter. There's been some additions to the language, like sealed classes and exhaustive switches, that could really benefit the implementation.
incognito124
I just went through this book during the winter holidays. I just love the author's casual writing style and all the tiny jokes and puns they made.

I hope we get to see "Add a type checker to Lox" sequel

wduquette
Simply my favorite programming text of all time.