nom VS pom

Just in case you are not familiar with nom, it is a parser combinator written in Rust. The most basic thing you can do with it is import one of its parsing functions, give it some byte or string input and then get a Result as output with the parsed value and the rest of the input or an error if the parser failed. tag for example is used to recognize literal character/byte sequences.

I may be the only one not familiar, but nom refers to https://github.com/rust-bakery/nom which looks like a pretty handy way to parse binary data in Rust.

Lots of people use nom for their parsing needs, but that's not the only game in town and there other options.

As much as I love nom as well as other parser combinator libraries, regex-based parsers, BNF/EBNF-based parsers, etc. I always end up going back to plain old text-based char-by-char scanners.

I am using nom / nom_locate to build the parser side because I've done a handful of other projects with it, and I plan to use tower-lsp to hook up the language server side.

Look into a parsing library such as https://github.com/rust-bakery/nom

If we were in /r/learnrust I'd have recommended the nom crate for this.

Thanks to the flexibility of [nom](https://github.com/rust-bakery/nom), it is very easy to write your own parser in rust, read [this article](https://github.com/metaworm/luac-parser-rs/wiki/Write-custom-luac-parser) to learn how to write a luac parser

I've been working on an assembler and right now it uses nom. While nom isn't great for error messages, good error messages will be important for this particular assembler (current code), so I've been attempting to use the methods described by Eyal Kalderon in Error recovery with parser combinators (using nom).

pom

Maybe a parser combinator library is not what you want? One alternative might be writing an expression parser without a library at all: https://matklad.github.io/2020/04/13/simple-but-powerful-pratt-parsing.html (Depending on the grammar you are parsing a Pratt parser might actually be a good fit!) A PEG might also be more suitable for your use case, like pom.

I saw the performance comparison against pom, pom is unfortunately quite slow compared to an handwritten parser as it boxes most (all?) parsers so you may want to compare against a handwritten parser, or at least something in the same ballpark (for reference, combine's json benchmark on the same data is about 6x faster with "good errors", when optimized to work on &str-like input it is about 12x faster, nom or a hand written parser may be another 10-20% faster than that, if I remember correctly.) From a brief skim of the code, I don't see anything that would hinder it from at least closing that gap however.

Everyone on this sub seems to be using nom. In my experience I find pom to be intuitive and have to write less code. Maybe it's just me I'm having a hard time understanding nom which has a lot of function calls rather than less.If you compare both the json examples on both projects, the pom example is a lot clearer to read and a lot shorter.