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Learn C and build your own Lisp

buildyourownlisp.com

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Re: Learn C and build your own Lisp

#21

Post by tomp »

jnbiche wrote: post #15
tomp wrote: post #5

In the last chapter, Bonus Projects, the author mentions Static Typing & type systems. If anyone's interested in learning more: I've implemented a few simple implementations of basic (and not so basic) type systems[1]. Currently, only 3 type systems are finished (Hindley Milner's Algorithm W, and Daan Leijen's extensible rows and first-class polymorphism), while gradual typing is almost done (based on [2], in branch…

Oh wow! This is extremely useful, thank you. I've been wanting to develop my own statically-typed language, but almost all tutorials on the web are for dynamic languages with little mention given to type systems. I've already started a toy dynamically-typed language, but the step up from that to a static language seems significant, particularly given the dearth of information I can find on the web (aside from dense a…

Well, the purpose of this project is purely to experiment with type systems, so this is far from a programming language (e.g. in a real compiler, you would want to save file/line information for AST nodes, so that the type-checker can report an error, not simply abort. Also, a compiler would not just type-infer/check the AST, but would annotate the AST with inferred types, so that they can be used in later stages (optimization, ...)). Shoot me an email if you need help with something. Also, check out [1].

> Please consider putting out a donation link so people can support your work (Bitcoin would be most convenient for me, but I'll definitely try to donate regardless).

I'd prefer comments/bugs/interesting discussion.

> Also, some kind of open source license would be great (MIT or BSD, maybe?).

I'll do that ASAP, in the meantime, it's public domain/CC-whatever, with the exception of file first_class_polymorphism/propagate.ml and propagation of types tests in first_class_polymorphism/test_infer.ml and first_class_polymorphism/test_infer.ml, which are heavily inspired by Daan Leijen's reference implementation.

[1] https://github.com/typeclassy/plzoo

Re: Learn C and build your own Lisp

#24

Post by orangeduck »

simias wrote: post #8
CGudapati wrote: post #2

How good is this book for a complete beginner? I am starting to learn C in my free time and I have no objective way to judge this book.

Skimming through the first chapters of the book I can say it doesn't seem to assume any prior knowledge of C or even a background in programming, it explains all the basic concepts (conditionals, types etc...) That being said I'm not entirely convinced that implementing a programming language is the best toy project for learning C since one of the first things you have to write is a parser and we all know string hand…

Author here. Actually a parser combinator library is used for the parsing. As you mention, I think there should be some interesting things inside for people with any experience in C.

Re: Learn C and build your own Lisp

#25

Post by gmfawcett »

jnbiche wrote: post #15
tomp wrote: post #5

In the last chapter, Bonus Projects, the author mentions Static Typing & type systems. If anyone's interested in learning more: I've implemented a few simple implementations of basic (and not so basic) type systems[1]. Currently, only 3 type systems are finished (Hindley Milner's Algorithm W, and Daan Leijen's extensible rows and first-class polymorphism), while gradual typing is almost done (based on [2], in branch…

Oh wow! This is extremely useful, thank you. I've been wanting to develop my own statically-typed language, but almost all tutorials on the web are for dynamic languages with little mention given to type systems. I've already started a toy dynamically-typed language, but the step up from that to a static language seems significant, particularly given the dearth of information I can find on the web (aside from dense a…

You might also enjoy Matías Giovannini's write-up of a typed concatenative language in Ocaml:

http://alaska-kamtchatka.blogspot.ca/2009/01/essence-of-conc...

Re: Learn C and build your own Lisp

#27

Post by jnbiche »

m_mueller wrote: post #20
jnbiche wrote: post #15

Earlier quoted context omitted.

Oh wow! This is extremely useful, thank you. I've been wanting to develop my own statically-typed language, but almost all tutorials on the web are for dynamic languages with little mention given to type systems. I've already started a toy dynamically-typed language, but the step up from that to a static language seems significant, particularly given the dearth of information I can find on the web (aside from dense a…

Something that might be useful for you: I've heard a talk where the speaker described how F# allows defining one's own type system as an input to the compiler. The language is apparently very extendible this way. It's also open source but I can't find information about its license just now. If I were to build a custom type system that's probably where I'd start to look at, even though I'm not a .NET developer.

Hmm, maybe he was talking about type providers? These let you "customize" F# (kind of like macros) but not really implement a new language.

But I'd definitely be interested in that talk if you can remember the name of the speaker or the venue/conference so I can try to Google it.

Re: Learn C and build your own Lisp

#28

Post by jnbiche »

tomp wrote: post #21
jnbiche wrote: post #15

Earlier quoted context omitted.

Oh wow! This is extremely useful, thank you. I've been wanting to develop my own statically-typed language, but almost all tutorials on the web are for dynamic languages with little mention given to type systems. I've already started a toy dynamically-typed language, but the step up from that to a static language seems significant, particularly given the dearth of information I can find on the web (aside from dense a…

Well, the purpose of this project is purely to experiment with type systems, so this is far from a programming language (e.g. in a real compiler, you would want to save file/line information for AST nodes, so that the type-checker can report an error, not simply abort. Also, a compiler would not just type-infer/check the AST, but would annotate the AST with inferred types, so that they can be used in later stages (op…

Oh, I know this project wasn't to create an entire compiler. But it's a great explanation of a missing puzzle piece in my own project.

Hope I didn't offend by suggesting donations -- wasn't my intent.

Anyway, thanks again for putting this out there. It will be a big help.

Edit: Wow, plzoo is another great resource, thank you. I found a reference to the plzoo project and website at one point but the site itself no longer seems operational ("no one here but us chickens", it says) and I didn't think the source code would be available anywhere. Very happy to see it's up on github.

Re: Learn C and build your own Lisp

#30

Post by mcmillhj »

jnbiche wrote: post #15
tomp wrote: post #5

In the last chapter, Bonus Projects, the author mentions Static Typing & type systems. If anyone's interested in learning more: I've implemented a few simple implementations of basic (and not so basic) type systems[1]. Currently, only 3 type systems are finished (Hindley Milner's Algorithm W, and Daan Leijen's extensible rows and first-class polymorphism), while gradual typing is almost done (based on [2], in branch…

Oh wow! This is extremely useful, thank you. I've been wanting to develop my own statically-typed language, but almost all tutorials on the web are for dynamic languages with little mention given to type systems. I've already started a toy dynamically-typed language, but the step up from that to a static language seems significant, particularly given the dearth of information I can find on the web (aside from dense a…

You can get a used copy of the Dragon book for relatively cheap. The PDF is probably floating around on the internet somewhere as well.
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