4 ms·

If you create whole new languages, i.e. external languages, not really embedded DSLs, with their own syntax, how is Racket better than other languages at implem

If you create whole new languages, i.e. external languages, not really embedded DSLs, with their own syntax, how is Racket better than other languages at implementing those? Neither the sntax object, nor hygiene are of concern when you build external DSLs, which the author's examples seem to be. I have not yet seen a compelling argument for Racket there vs. for instance a parser generator framework. I might just be missing the point. Either way the author's convincing seemed to have failed for me.

choeger 8y ago
I think racket makes it simple to compose your language implementation modules. So e.g., hygiene could be imported (with minimal adaptions to your syntax/binders).
- quelltext 8y ago
  Yeah, that's true. I would love to read an article about that with practical examples, i.e. showing that language composition is really a common and needed pattern (not just a theoretic concern, ... are LOP users really composing several language modules often?), and how Racket enables it.
  - elizabeth_olu 8y ago
    https://www.elizabethblog.com.ng/2019/02/maduguri-in-explosion-as-boko-haram.html https://www.elizabethblog.com.ng/2019/02/maduguri-in-explosi...
  - Rasyidsugar 8y ago
    By the way I wrote an article about an English grammar. maybe it could be useful for you .. https://www.tolongtangtugas.web.id/2019/02/master-present-perfect.html https://www.tolongtangtugas.web.id/2019/02/master-present-pe...
pge 8y ago
In LISP-like languages like Racket, the code is a list. That is, a program is just a list of tokens (a b c), the same data structure one would use for storing any other kind of data (the equivalent of Python’s [a b c]). When programs are themselves just lists, they are easy to manipulate with code. So, in LISP-like languages, it is easy to write code that writes code. That makes them especially suitable for domain-specific languages or LOP. You can write functions that write code, making a new language. I think PG has some writings on this topic, but I don’t remember if it is online or in his LISP textbooks. His company Viaweb did this, IIRC, using a DSL written in LISP to generate HTML.
- deleted 8y ago
  [deleted]
- amelius 8y ago
  > In LISP-like languages like Racket, the code is a list. This is nothing special. In all languages, code is a list: a list of characters, that is. Just saying.
  - mgfist 8y ago
    LISP code is not a list as you know it traditionally. It's made up of cons cells. The code of other languages is not a cons cell, altho it is a list of characters. Very important distinction.
  - adjkant 8y ago
    A list of characters (a string) and a list of tokens are drastically different to work with. If you haven't worked with both and want to write programming languages, I would recommend filling the gap of the one you haven't to see/feel the difference. Beyond the code being a list, Racket's macro system and syntax parse / creation tools are incredibly powerful and come built in where you could spend years in another language just getting the tooling to write a language, let alone writing it.
  - krapp 8y ago
    What the parent likely means is that Lisps, structurally, are akin to the AST many other languages generate as an intermediate step to compilation.
agumonkey 8y ago
sharing ?
gilmi 8y ago
Alexis King covers some of the benefits in one of her blog posts about Hackett[0] and in her talk Languages in an Afternoon[1]. [0]: https://lexi-lambda.github.io/blog/2017/01/05/rascal-is-now-hackett-plus-some-answers-to-questions/ https://lexi-lambda.github.io/blog/2017/01/05/rascal-is-now-... [1]: https://youtube.com/watch?v=TfehOLha-18 https://youtube.com/watch?v=TfehOLha-18
spacesuitman2 8y ago
>I have not yet seen a compelling argument for Racket there vs. for instance a parser generator framework. Racket allows for easy interop between the various languages, so for instance, you can use typed racket from untyped modules. You can import documentation modules in base racket and so on. With other languages, you have to glue the infrastructure yourself, racket does it for you.
mst 8y ago
A parser generator is m-expressions to racket's s-expressions - which is all about syntax, whereas s-expr based DSLs are focused on semanics. Not sure if that makes anything clearer but I can't think of a better phrasing.

choeger 8y ago

I think racket makes it simple to compose your language implementation modules. So e.g., hygiene could be imported (with minimal adaptions to your syntax/binders).

quelltext 8y ago
Yeah, that's true. I would love to read an article about that with practical examples, i.e. showing that language composition is really a common and needed pattern (not just a theoretic concern, ... are LOP users really composing several language modules often?), and how Racket enables it.
- elizabeth_olu 8y ago
  https://www.elizabethblog.com.ng/2019/02/maduguri-in-explosion-as-boko-haram.html https://www.elizabethblog.com.ng/2019/02/maduguri-in-explosi...
- Rasyidsugar 8y ago
  By the way I wrote an article about an English grammar. maybe it could be useful for you .. https://www.tolongtangtugas.web.id/2019/02/master-present-perfect.html https://www.tolongtangtugas.web.id/2019/02/master-present-pe...

pge 8y ago

In LISP-like languages like Racket, the code is a list. That is, a program is just a list of tokens (a b c), the same data structure one would use for storing any other kind of data (the equivalent of Python’s [a b c]). When programs are themselves just lists, they are easy to manipulate with code. So, in LISP-like languages, it is easy to write code that writes code. That makes them especially suitable for domain-specific languages or LOP. You can write functions that write code, making a new language. I think PG has some writings on this topic, but I don’t remember if it is online or in his LISP textbooks. His company Viaweb did this, IIRC, using a DSL written in LISP to generate HTML.

deleted 8y ago
[deleted]
amelius 8y ago
> In LISP-like languages like Racket, the code is a list. This is nothing special. In all languages, code is a list: a list of characters, that is. Just saying.
- mgfist 8y ago
  LISP code is not a list as you know it traditionally. It's made up of cons cells. The code of other languages is not a cons cell, altho it is a list of characters. Very important distinction.
- adjkant 8y ago
  A list of characters (a string) and a list of tokens are drastically different to work with. If you haven't worked with both and want to write programming languages, I would recommend filling the gap of the one you haven't to see/feel the difference. Beyond the code being a list, Racket's macro system and syntax parse / creation tools are incredibly powerful and come built in where you could spend years in another language just getting the tooling to write a language, let alone writing it.
- krapp 8y ago
  What the parent likely means is that Lisps, structurally, are akin to the AST many other languages generate as an intermediate step to compilation.

agumonkey 8y ago

sharing ?

gilmi 8y ago

Alexis King covers some of the benefits in one of her blog posts about Hackett[0] and in her talk Languages in an Afternoon[1]. [0]: https://lexi-lambda.github.io/blog/2017/01/05/rascal-is-now-hackett-plus-some-answers-to-questions/ https://lexi-lambda.github.io/blog/2017/01/05/rascal-is-now-... [1]: https://youtube.com/watch?v=TfehOLha-18 https://youtube.com/watch?v=TfehOLha-18

spacesuitman2 8y ago

>I have not yet seen a compelling argument for Racket there vs. for instance a parser generator framework. Racket allows for easy interop between the various languages, so for instance, you can use typed racket from untyped modules. You can import documentation modules in base racket and so on. With other languages, you have to glue the infrastructure yourself, racket does it for you.

mst 8y ago

A parser generator is m-expressions to racket's s-expressions - which is all about syntax, whereas s-expr based DSLs are focused on semanics. Not sure if that makes anything clearer but I can't think of a better phrasing.