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Crafting Interpreters

craftinginterpreters.com

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Re: Crafting Interpreters

#71

Post by shortercode »

Arisaka1 wrote: post #66

Curious question from someone new to the programming field who lacks a formal CS background: How are books like this one are meant to be consumed? Do you read it cover to cover as you code along with the author in a way YouTube tutorials work? The main reason for asking is, I don't know if I'm lacking in natural gifts (really likely) but I can't seem to retain knowledge like that. It feels nice to onboard myself to a…

This book is intended to be a cover to cover job. I tackled it about 2 or 3 chapters at a time while building alongside. But after the midway point where it swaps to a C based byte code compiler I just read it instead.

There are books like the dragon book which cover PL design in a more reference book style. But I don’t recommend them.

If you’re looking for a lighter alternative then “writing an Interpreter in Go” is worth a look.

Also Bob Nystrum has some other good material on his blog, and a chapter in game programming patterns about PL stuff.

Re: Crafting Interpreters

#72

Post by aodonnell2536 »

Arisaka1 wrote: post #66

Curious question from someone new to the programming field who lacks a formal CS background: How are books like this one are meant to be consumed? Do you read it cover to cover as you code along with the author in a way YouTube tutorials work? The main reason for asking is, I don't know if I'm lacking in natural gifts (really likely) but I can't seem to retain knowledge like that. It feels nice to onboard myself to a…

Well, in the instance of this book, you should follow along with the steps that Bob Nystrom writes for you. From reading it, it’s clear you’re supposed to follow along and write code “with him”. He even outlines exactly where each line of code should go, and explains why along the way.

Re: Crafting Interpreters

#73

Post by fmbb »

chasil wrote: post #10

The lex and yacc utilities are part of POSIX.2; is there any reason not to reach for them first? https://pubs.opengroup.org/onlinepubs/9699919799/utilities/l... https://pubs.opengroup.org/onlinepubs/9699919799/utilities/y... All the POSIX.2 standards for shell utilities can be found here: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/ The original introduction to lex and yacc was in the book by Kernigan…

Is there any reason to reach for them first?

Re: Crafting Interpreters

#74

Post by myco_logic »

news_to_me wrote: post #26
liamilan wrote: post #21

Read Crafting Interpreters when building Crumb ( https://github.com/liam-ilan/crumb ). It was indispensable, especially the sections on scope and local variables. The balance between technical implementation and conceptual insights is super helpful, especially when trying to go off of the book’s set path. It’s inspiring to see technical writing done like this. As an aspiring engineer, this sets a really high standard…

This looks cool! How did you decide on what data types to include?

Personal choice, is what I'd say. You can get a lot of mileage out of implementing a dynamic language with NaN boxing[1].

It really depends on the kind of language you're trying to build an interpreter for, and what purpose it could serve. For dynamic languages, I'd say looking at the core types of Erlang is a great place to start (Integers, Symbols, Functions, etc.). For a statically typed language things get more complex, but even with just numeric types, characters, and some kind of aggregating type like a Struct you can build up more complex data structures in your language itself.

[1]: https://leonardschuetz.ch/blog/nan-boxing/

Re: Crafting Interpreters

#75

Post by foooorsyth »

Arisaka1 wrote: post #66

Curious question from someone new to the programming field who lacks a formal CS background: How are books like this one are meant to be consumed? Do you read it cover to cover as you code along with the author in a way YouTube tutorials work? The main reason for asking is, I don't know if I'm lacking in natural gifts (really likely) but I can't seem to retain knowledge like that. It feels nice to onboard myself to a…

This book, unlike the infamous “Dragon Book” for compilers, can be read cover to cover. The Dragon Book has great detail but it is a slog, especially in early chapters. So many students drop their first course on compilers every year because of the Dragon Book and not the actual concepts

Re: Crafting Interpreters

#76

Post by fooker »

This book should be the second or maybe third step of your journey into PL compilers.

The first step is to write an interpreter yourself, for a simple language you create, without knowing anything about interpreters or language design. The second step is to rewrite it, and make less mistakes! :)

If you don't do this, you are never going to appreciate the nuances of this topic. And you are going to skip over concepts that don't seem important.

Re: Crafting Interpreters

#77

Post by bruce343434 »

fooker wrote: post #76

This book should be the second or maybe third step of your journey into PL compilers. The first step is to write an interpreter yourself, for a simple language you create, without knowing anything about interpreters or language design. The second step is to rewrite it, and make less mistakes! :) If you don't do this, you are never going to appreciate the nuances of this topic. And you are going to skip over concepts…

For me, this book demystified these topics and allowed me to do your second and third step in the first place :)

It's okay to not come up with/reinvent from first principles every technique on your own. It's normal to stand on the shoulders of giants.

Re: Crafting Interpreters

#78

Post by rnart »

runevault wrote: post #29
chasil wrote: post #10

The lex and yacc utilities are part of POSIX.2; is there any reason not to reach for them first? https://pubs.opengroup.org/onlinepubs/9699919799/utilities/l... https://pubs.opengroup.org/onlinepubs/9699919799/utilities/y... All the POSIX.2 standards for shell utilities can be found here: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/ The original introduction to lex and yacc was in the book by Kernigan…

Does a single production compiler use lex and yacc to generate any part of their system, beyond maybe a first pass to test out syntax before it gets rewritten into a hand written parser/lexer? I'm not going to say none exist since I don't know literally every production compiler ever written, but I have never heard of one that used them for the final code.

Yes, OCaml with its very complex syntax and hundreds of features uses the OCaml equivalents of Lex/Yacc. It is a myth that one cannot use Lex/Yacc in production.

Re: Crafting Interpreters

#79

Post by rnart »

gavinhoward wrote: post #11
chasil wrote: post #10

The lex and yacc utilities are part of POSIX.2; is there any reason not to reach for them first? https://pubs.opengroup.org/onlinepubs/9699919799/utilities/l... https://pubs.opengroup.org/onlinepubs/9699919799/utilities/y... All the POSIX.2 standards for shell utilities can be found here: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/ The original introduction to lex and yacc was in the book by Kernigan…

As the author of a POSIX standard utility, I would advise you to only reach for such utilities when portability is the most important thing. POSIX utilities are not great. Lex and Yacc included.

I disagree here. The syntax can be infuriating at first, but once you understand it, Lex/Yacc are rock solid and speed up development significantly.

Re: Crafting Interpreters

#80

Post by SatvikBeri »

alabhyajindal wrote: post #35

I really wish this book used something other than Java. Nothing against Java - just that I don't know it and don't feel excited about learning it.

Lots of people have done implementations in other languages: https://github.com/munificent/craftinginterpreters/wiki/Lox-...

I did the first half in Clojure (in order to teach myself Clojure), worked just fine. I had to do a bit of translation but it's really not a lot.

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