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Comment by steveklabnik | Hacker News Reader

Rust doens't have objects. (Trait objects kind of come close but are very rare and I've never used one with Diesel.)

I think if you read the post, you'll see that Diesel is very data-driven.

Personally, I tend to call it a "query builder" if I think someone might be ORM-phobic; I find it closer to that than other ORMs, even though it's authored by the maintainer of one of the most massively popular ORMs ever. They've sometimes joked that that experience has taught them what not to do ;)

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Given the previous experience of authoring a popular ORM, why repeat the mistake of pluralization of table names from model names?

I've always found this convention to be problematic at best and I've learned to avoid it. Maintaining consistency of names inside and outside of code makes searches and references easier to follow without having to mentally (or even mechanically) expand the singular name to plural name or vice versa (say, in a scratch pad to compose a test query).

I guess not everyone considers that a mistake, but at least it's very easy to change; tack on a #[table_name="whatever"] and you're done. I'm not sure if there's a more global way, since I don't mind pluralization.

Yeah, it's just my opinion tempered with experience.

Is the pluralization rule literally as simple as stated in the article, namely appending an 's' and calling it done? English is rarely so simple and there are tons of corner cases which is why I tend to frown on the pluralization rules that are unpredictable. Those must be a nightmare for English-as-a-second-language folks too.

Oh yeah, I remember thanks to ActiveSupport::Inflector, heh.

Yes: https://github.com/diesel-rs/diesel/blob/e52d1710d98a05c3aa4...

But it also converts CamelCase to snake_case: https://github.com/diesel-rs/diesel/blob/e52d1710d98a05c3aa4...

> even though it's authored by the maintainer of one of the most massively popular ORMs ever

Just curious, what ORM is that?

ActiveRecord. Referencing it is a double-edged sword; Diesel is very much not ActiveRecord, so by saying it up front, people tend to get the wrong impression.

IThat's cool, didn't realise it was the same author.

I understand. The other side of that coin though I guess is that knowing this might give some more confidence in using diesel. ActiveRecord was the first ORM I used, and knowing now that diesel is "from the same stock" (for want of a better phrase) gives some extra confidence in what it can do / where it is going.

Not that I was not confident in it before...

Yup, absolutely, that's the other side of the sword :)

Indeed, the flood of Rails people who went over to Rust have definitely given some people pause to consider the direction it was taking.

I don't see this particular case of someone who spent a significant amount of time coding core Rails OSS library being seen as a negative though, quite the opposite. If anything it would be an excellent measure of the language for that particular use case assuming any competent developer would seek to operate in the constraints of the language rather than shoehorning an existing implementation into something that doesn't fit.

The bigger question is whether the ORM label itself is limiting or can be understood to fit into a broader scope of implementations.

I think people read way too much into the ORM label. Diesel is very much a query builder first, not an ORM. As a random data point, I've been fixing bugs in Rails lately by basically copying over code from Diesel and converting it to Ruby. That code has all been in Arel not Active Record.

I agree that the "I make Rails" thing is a double edged sword. I would hope people would see it as an indicator that I have a lot of experience and lessons to learn from, but I think many people see the opposite.

Thoughts on replacing Arel with Diesel + Helix[0]?

[0] https://github.com/tildeio/helix - When Helix can handle that complexity (if it can't already)

https://github.com/rails/rails/tree/master/activerecord

Thanks for clarifying. A subjective note, the executed SQL is way more beautiful than the Rust code ;) and to me, defines the intention better, a nicer approach to me would be if the syntax/grammar would have been more SQLish.

One benefit of the diesel approach is that it's type safe, whereas the pure SQL approach isn't.

There is no technical reason why you couldn't create a fully typesafe pure SQL interface in Rust, the same way Rust's format language is typesafe.

This is true, but to do that, you need procedural macros, which are not yet stable.

Ironically, I was actually originally planning on having Diesel primarily built around parsing actual SQL. (See the commit message of https://github.com/diesel-rs/diesel/commit/2ba8bf481c3d21d8b..., which is like commit number 4)

I agree that if you're just writing a single self-contained query, SQL is a great DSL for that. I've been trying to improve our story for working with raw SQL (one tradeoff will be that it isn't type checked).

However, there are major benefits to an in-language DSL as well. If you are wanting to re-use fragments of queries, or conditionally construct a different query, that's a pain to do with SQL strings.

You don't need to work with SQL strings though, you can work with ASTs or other higher level abstractions, and with Rust's macros and the infer_schema! machinery you can probably find a way to project the SQL types into Rust's type systems to keep things more or less type-safe. But then again, I've never tried to write such a thing, so maybe it's not quite as easy as that. I've definitely used a similar query-builder library in the past though and while it definitely had its benefits over raw SQL, it also led to some abuses where bits and pieces were used to compose gargantuan queries that nobody would have ever thought to write by hand.

> it's authored by the maintainer of one of the most massively popular ORMs ever

Cool, didn't know Sean Griffin maintained Hibernate!

I'm not sure what you're saying, I put a "one of" in there for a reason. I'm not particularly interested in debating which ORM is the most popular, but it's undeniable that ActiveRecord is in the set of ones you'd be considering if you were trying to answer that question.

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