Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Elo – A data expression language which compiles to JavaScript, Ruby, and SQL

elo-lang.org

Post reply on HN
Print view View original

11–20 of 36 posts

Re: Elo – A data expression language which compiles to JavaScript, Ruby, and SQL

#11

Post by geoffschmidt »

gatapia2 wrote: post #9
egonschiele wrote: post #8

Maybe the most incredible part – did Claude write a recursive descent parser from scratch for this? https://github.com/enspirit/elo/blob/9f07fefcdf65c169089f123... Not that it's super complex, but I'm surprised it didn't pick up an npm package. I wrote tarsec[1] and have been eyeing ohmjs[2]. And of course nearley is a classic. [1] https://github.com/egonSchiele/tarsec [2] https://ohmjs.org [3] https://nearley.js.org

That git commit is very impressive (for Claude) Edit: Oh, I think the main dev is just using Claude to do the commits (I guess to summarise changes, etc). It does not mean that Claude wrote all that code.

FWIW, at the bottom of the landing page they credit Claude for “every line of code, tests, and docs”

Re: Elo – A data expression language which compiles to JavaScript, Ruby, and SQL

#13

Post by blambeau »

swrobel wrote: post #6
h1fra wrote: post #4

Love the idea, but I don't think this "built for [...] non-technical users" works. All the examples were more confusing to me vs a regular programming language and definitely not accessible to non-technical users. Also, why would I want to compile to multiple languages? If I'm building a no-code platform, I won't bother supporting 3 different languages since I'm the only one seeing the code.

Yeah, P30D as presumably intuitive to non-technical users has me chuckling Also, knowing that TODAY > signup + P30D transpiles to TODAY > signup + 30.days in Ruby. Which one is more readable?

Point taken. Will see what I can do.

Probably TODAY + Duration({ days: 30 }) would be a better example then.

Re: Elo – A data expression language which compiles to JavaScript, Ruby, and SQL

#14

Post by blambeau »

gatapia2 wrote: post #9
egonschiele wrote: post #8

Maybe the most incredible part – did Claude write a recursive descent parser from scratch for this? https://github.com/enspirit/elo/blob/9f07fefcdf65c169089f123... Not that it's super complex, but I'm surprised it didn't pick up an npm package. I wrote tarsec[1] and have been eyeing ohmjs[2]. And of course nearley is a classic. [1] https://github.com/egonSchiele/tarsec [2] https://ohmjs.org [3] https://nearley.js.org

That git commit is very impressive (for Claude) Edit: Oh, I think the main dev is just using Claude to do the commits (I guess to summarise changes, etc). It does not mean that Claude wrote all that code.

Claude did, I swear

The parser was built gradually though, with logs of increments under automated tests.

Re: Elo – A data expression language which compiles to JavaScript, Ruby, and SQL

#17

Post by blambeau »

jauntywundrkind wrote: post #2

I really like this idea! I wish I knew other data expression engines for js. I feel like adding filtering languages into our http endpoints is one of those forever bespoke tasks. This is probably not the right form for tackling that problem, since it is a fairly complex query language & processor and doesn't cleanly map to something we'd use in a URL query string. But it makes me miss odata a little bit. And it makes…

Check finitio.io

Might be an alternative with less complexity for a simple filtering use case.

Re: Elo – A data expression language which compiles to JavaScript, Ruby, and SQL

#20

Post by torginus »

egonschiele wrote: post #8

Maybe the most incredible part – did Claude write a recursive descent parser from scratch for this? https://github.com/enspirit/elo/blob/9f07fefcdf65c169089f123... Not that it's super complex, but I'm surprised it didn't pick up an npm package. I wrote tarsec[1] and have been eyeing ohmjs[2]. And of course nearley is a classic. [1] https://github.com/egonSchiele/tarsec [2] https://ohmjs.org [3] https://nearley.js.org

Recursive descent parsers are basically mechanical structures, if you get the grammar right (which encapsulates all the logic).

When I was a CS student, they seemed like magic to me as well, but later I got to revisit them for a project at work, and finally managed to understand the logic.

Imo, the biggest complexity in using them comes from how they handle operator precedence, with recursive nested expressions in the grammar, which I still don't find intuitive at all.

If you decide to hand-roll your own parser/syntax today, I recommend you look at Pratt-parsers, they are much nicer to write by hand. Modern languages (Rust, Go) , ironically are much simpler to parse, since they defined the syntax in such a way that they can be parsed unambigously by looking 1-2 tokens ahead.

And since all of them follow the same logic, AI has a ton of sources to learn from.

I'm also working on my programming language, and AI assistants have been able to generate these parsers for well over a year.

Post reply on HN