lalrpop VS cue

And some related parser tools: - https://github.com/kevinmehall/rust-peg - https://github.com/pest-parser/pest - https://github.com/lalrpop/lalrpop

lalrpop

Rust is a very nice langage for implementing compilers, and has a nice ecosystem for it (logos, rust-peg, lalrpop, astmaker -- this one is mine --, etc...).

rust-langdev has a lot of libraries for building compilers in Rust. Perhaps you could use these to make your implementation easier, and revisit it later if you want to build things from scratch. I'd suggest logos for lexing, LALRPOP / chumsky for parsing, and rust-gc for garbage collection.

Hi! For one of my projects I am currently using lalrpop (https://github.com/lalrpop/lalrpop/tree/master/doc/calculator/src), which is far from complete, but has the basic syntax I was looking for. I took some examples and worked around some lexer stuff but I’m currently happy with it. If you use it and have Intellij stuff installed, you can also use a plug-in for highlighting and SOMETIMES error checking. Otherwise, even VSCode had a great plug-in for highlighting!

How would you compare and contrast this with, say, lalrpop?

lalrpop is great. It's a completely different approach from nom, but for parsing a programming language, I would at least consider it. RustPython uses it.

I presume LALRPOP handles left recursion just fine.

I wanted to share an experimental side project I have been working on for some time. I constantly use commands like `jq` and `yq` for processing structured data in my day job and I was curious if a similar idea could be applied to images.

Another goal of mine was to get some exposure to with rust. I discovered the LALRPOP parser generator which really helped moved the project along (https://github.com/lalrpop/lalrpop)

The key point here is that we are going to depend on the lalrpop library to generate the parser based on the formal grammar we define. Note that we have it as part of the [build-dependencies] section and we only depend on a tiny utility crate called lalrpop-util at runtime. The reason for that is the main lalrpop "magic" would happen during the crate compilation (in the build.rs file) when lalrpop would generate the deterministic pushdown automaton based on our grammar. The code generation logic is not required to be part of our interpreter, we only need a few utility methods from the lalrpop-util for the automaton to operate. You might have noticed that we also enable the lexer feature of lalrpop, because we are going to use lexer provided by lalrpop as well (please refer to the Part I if you do not know what the lexer is).

I'm continuing to work on https://concise-encoding.org which is a new security-conscious ad-hoc encoding format to replace JSON/XML and friends. I've been at it for 3 years so far and am close to a release.

In a nutshell:

- Edit in text, transmit in binary. One can be seamlessly converted to the other, but binary is far more efficient for processing, storage and transmission, while text is better for humans to read and edit (which happens far less often than the other things).

- Secure by design: Everything is tightly specced and accounted for so that there aren't differences between implementations that can be exploited to compromise your system. https://github.com/kstenerud/concise-encoding/blob/master/ce...

- Real type support because coercing everything into strings sucks (and is another security risk and source of incompatibilities).

XML had a good run but was replaced by JSON which was a big improvement. JSON also had a good run but it's time for it to retire now that the landscape has changed even further: Security and efficiency are the desires of today, and JSON provides neither.

I've got the spec nailed down and can finally see the light at the end of the tunnel for the reference implementation in golang. I still need to come up with a system for schemas, but I'm hoping that https://cuelang.org will fit the bill.

Has anyone taken a look at Cue who can share any experiences?

https://cuelang.org/

It's mentioned on the site as an alternative to Yaml. Recently watched (~half of) this intro to it: https://youtu.be/fR_yApIf6jU

the most interesting summary explanation of cue lang and its differences is from a bug filing - https://github.com/cuelang/cue/issues/33

>CUE is a bit different from the languages used in linguistics and more tailored to the general configuration issue as we've seen it at Google. But under the hood it adheres strictly to the concepts and principles of these approaches and we have been careful not to make the same mistakes made in BCL (which then were copied in all its offshoots). It also means that CUE can benefit from 30 years of research on this topic. For instance, under the hood, CUE uses a first-order unification algorithm, allowing us to build template extractors based on anti-unification (see issue #7 and #15), something that is not very meaningful or even possible with languages like BCL and Jsonnet.

I agree with you. Personally, I think Cue is much better than either YAML, TOML or JSON because it adds the concept of types to the idea of describing configuration.

true, but the tooling and workflow remains the same.

Not sure of any tool that could abstract the details sufficiently to be widely adopted. There is just too much nuance in cloud config.

I'm exploring using CUE (https://cuelang.org) to define TF resources, exporting as JSON for TF. So far it's much nicer