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There is definitely room for a scheme compiler. But the scheme ecosystem felt extremely fractured the last time I took a look. Chicken had a decent but aging repo. Chez had a great compiler (I prefer not compiling to C) but it's package ecosystem was not something well advertised if it did have one. Racket has too many dialects which might appeal to some but found the number of sub languages overwhelming for a casual schemer.

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Making languages is the thing that Racket does better than any other language, so they do tend proliferate. However, for getting stuff done the majority of work is done in just Racket. You don't need to know the other languages unless you're interested in some specialist task they target.

Back when I was a regular Scheme user Racket had by far the biggest ecosystem and community, so it would be my suggestion if you're interested in exploring Scheme.

>Making languages is the thing that Racket does better than any other language

Have you tried Rebol/Red?

I have not.

They basically have PEG-kind of parser built into the language allowing you to execute arbitrary code up to modifying the parsing rules themselves.

Here's small shell dialect I made while learning it: https://gitlab.com/maxvel/red-shell-dialect/blob/master/shel...

So you can do things like

  shell/run [cat %/etc/passwd | grep {root} > myvar]

where both `cat` and `grep` can be either shell commands or Red functions and you can redirect input/output from/to variables as well as files. Also you can mixin Red data types, like in example here `%/etc/passwd` is a file instance, not a string.

Also the language itself heavily utilizes this (called Parse dialog) for example they don't have regular expressions at all, JSON is parsed using it as well, GUI system is a fully separate dialog and so on.

s/dialog/dialect/

Concept of a dialect (aka 'embedded DSL') is not tied to Parse - you can implement one with it for sure, but it's not a strict requirement.

I did and even though I'm forever in love with both Rebol and Red, Racket does languages in a more fun way and powerful way for my own personal taste. Don't know if you have checked this book out but https://beautifulracket.com/ is a wonderful introduction for building languages with Racket.

From brief check on the book I see that Racket has a lot of infrastructure for making languages, but fundamentally I don't see the difference with Parse in Red. One can easily add tokenizer, reader and expander similar to what is there in Racket.

For me, the power of the Redbol approach lies in the rich set of datatypes, so you can create dialects at the block/value level, leveraging the syntax without having to tokenize at the string level. It's no small thing to be able to create languages that natively understand values like email addresses, URLs, IP addresses, files as distinct from strings, and more.

I tried it and would consider it a write-once language, similar to Forth in that respect. It seems good for quick hacks but not for long-term maintainable projects.

Can you elaborate?

I'd like more info on that as well (as part of Team Red). And, for comparison, what language(s) you feel are best for that, and what features lead to that.

For those that haven't used Rebol or Red. It is a homoiconic language like lisp, but no s-expressions as I understand it.

Rebol is really nice with a lot of built-in primitives that make it super useful although Rebol is kind of dead now (some users exist, but no new versions in a while). Red is being worked on and if it ever reaches 1.0 could be a game changer.

I think it is pretty easy to build little DSLs, but I don't think macros are super easy unless I'm mistaken. If somebody could shed some light for me I'd appreciate it.

You don't need macros in Red (but it's easy to roll out your own macro layer, if one so desires [1]), all code transformations can be achieved at runtime. A brief explanation of how this works is given in [2].

As for Red / Rebol vs. Racket content - I wrote an excessive post on that some time ago [3], in response to similar question.

TL;DR from language creation perspective is that Racket has state-of-the-art macro system and all the necessary infrastructure, and Red has metaDSL (that is, DSL for creating DSLs) called Parse [4], which is basically PEG on steroids (think OMeta) + a different take on homoiconicity, compared to Lisps, which, most of the time, renders custom readers and tokenizers unnecessary.

[1]: https://www.red-lang.org/2016/12/entering-world-of-macros.ht...

[2]: https://github.com/red/red/wiki/%5BNOTES%5D-How-Red-Works---...

[3]: https://www.reddit.com/r/redlang/comments/aebxct/contrast_re...

[4]: https://www.red-lang.org/2013/11/041-introducing-parse.html

> Back when I was a regular Scheme user Racket had by far the biggest ecosystem and community,

IIRC, you were instrumental in building the ecosystem, and attracting many other contributing community members.

Network effects bootstrapping blame, where it's due. :)

Ha! I blame you! :-)

Nobody else does! :)

Does anyone use Racket outside academia/hobby?

Yes.

https://www.greghendershott.com/2018/05/extramaze-llc-using-...

https://defn.io/2019/08/20/racket-ecommerce/

Yes. I've written a test framework for another software I'm developing that (optionally) sets up an environment for the executable under test, (optionally) launches and monitors the executable (process state, stderr/stdout), connects to the process via a WebSocket (that's what that executable does) and then tests the surface of the exposed WS-API. As the executable runs under windows & linux, embedded and not, this approach lets me run the test suite under all different hosts and connect to localhost or the thing running elsewhere. So, in my case, you may not see it in a product; but the product we're building is continuously tested with a myriad of racket programs.

Racket 7.4 now comes running on chez if you so wish. Check out [1]. In there there's also the links to the whys, hows and whats of the whole effort.

I've been using racket quite a lot lately, really like it. The thing I do not like about racket is the whole "racket 2" effort. Abandon S-exps? Really? To leave behind the 'popularity boundaries' of lisps? d'oh How about you drop your common USP that you share with the other lisps to become .. what, exactly.. irrelevant?

Cf. your 'dialect' point: In reality, the languages are just (supposed to be) DSLs for specific (sub-)problems of your problem-space. I don't mind, at all. You just require the libraries written in that other dialect from racket and use the stuff in there, et voila.

[1] https://blog.racket-lang.org/2019/08/racket-v7-4.html

I always thought that was the best feature of scheme. Nobody agrees on anything, except mainly R5RS, keeping it from going down the path of "one implementation for everything, always" that most languages suffer from once they become a little popular. Scheme is one of the very few languages that has resisted accruing a lot of bloat throughout its existence (R6RS never was very popular because of that)

People underestimate the upside of being able to paste any example snippet into your repl and have it work transparently in almost every scheme, without having to worry about libraries or eco-systems.

For anything more exotic, you grab the nearest SRFI and squeeze it around until it works in the scheme you're working with.

Scheme: it's so simple, any subgenius could use it!

I am just getting into Scheme, and have heard good things about Chez. Any pointers to what is standard out in the wild? What are the de-facto Scheme tools are people using these days?

I just got into Scheme this past month, but I started with GNU Guile, and really like it.

https://akkuscm.org/ is a seemingly vibrant package manager for Chez and others. It is also by the author of the article.

The story of Scheme is that it was so easy to implement (relatively) that they ended up with dozens of implementations, so they decided to write a standard... and then started doing the same thing with the standard(s).

It's a language family, or even philosophy, rather than a single language.

The standard was quite ok, until the version 7 disagreement of what should be actually in.

There's always been disagreement. R7RS (small|large) is an effort to resolve that disagreement.

I thought that R7RS was the one that sparked it.

R6RS was the one that really sparked the divide, and for a long time only had a limited number of implementations due to this controversy. The big thing that R6RS brought, in my opinion, was a syntax for creating modules and sharing them. R7RS was an attempt to create an R5RS-like minimal standard that still had a library/module syntax so that you could get a bunch of implementations and share code between them. R7RS-small did this, and then R7RS-large attempts to use the module syntax to create a big body of "industrial strength" code that you can use to get "real things" done with scheme. The R7RS-large process seems to be using the SRFIs as a staging ground for the new modules, standardizing on chunks of them as they go in different "editions".

So the theory now is that you can write a smaller R7RS-small compliant scheme, and do all your language experimentation in that, and someone else could come along and bootstrap that into a fairly useful large implementation without a ton of effort, and modules you write on that scheme could then be reused on other implementations.

Likewise, thanks for clarifying it as well.

There are three ways to think about this.

1. R7RS explicitly decided to repudiate R6RS, leading to the disagreement.

2. R6RS made changes that did not have consensus and the resulting vote didn't have a big enough super majority requirement, leading to a controversial standard.

3. There was always major disagreement about all the relevant points, and R5RS itself was only created by not introducing anything new post 1992, and by not taking a position on the controversial topics. So any standard effort was bound to be controversial.

Thanks for clarifying it.

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