Having issues using this library

[spf5000]

I was hoping to use this library to build an abnf "parser generator". I was going to use this library to parse the abnf, then use the types from this library to generate a parser for the given abnf language. However, I've been unable to parse a relatively simple statement from an abnf language I'm trying to parse to test with:

    let rule = match rulelist("idl = ws control_section metadata_section shape_section\n") {
        Ok(rule) => rule,
        Err(err) => { eprintln!("{:?}", err); return Err(anyhow::Error::new(err))}
    };
    println!("{:#?}", rule);

I'm getting:

Error: Error(VerboseError { errors: [("idl = ws control_section metadata_section shape_section\n", Nom(CrLf)), ("idl = ws control_section metadata_section shape_section\n", Nom(Alt)), ("idl = ws control_section metadata_section shape_section\n", Nom(Alt)), ("idl = ws control_section metadata_section shape_section\n", Nom(Many1))] })
ParseError { message: "Error(VerboseError { errors: [(\"idl = ws control_section metadata_section shape_section\\n\", Nom(CrLf)), (\"idl = ws control_section metadata_section shape_section\\n\", Nom(Alt)), (\"idl = ws control_section metadata_section shape_section\\n\", Nom(Alt)), (\"idl = ws control_section metadata_section shape_section\\n\", Nom(Many1))] })" }

I'm using linux to run this code, so maybe there is something going on there? It seems like it doesn't ever find a newline character? I like what you're doing with this library and would love to leverage it for my own project, but I'm new to parsing and not sure what's going on here.

[duesee]

Hey, the reason why you get an error is because ABNF does not allow _ in non-terminals.

rulename = ALPHA *(ALPHA / DIGIT / "-")

Using idl = ws control-section metadata-section shape-section\n yields the correct result:

[
    Rule {
        name: "idl",
        node: Concatenation(
            [
                Rulename(
                    "ws",
                ),
                Rulename(
                    "control-section",
                ),
                Rulename(
                    "metadata-section",
                ),
                Rulename(
                    "shape-section",
                ),
            ],
        ),
        kind: Basic,
    },
]

You should also Display the error in line 3 and not Debug it. When you change {:?} to {}, it will print

0: at line 1, in CrLf:
idl = ws control_section metadata_section shape_section
^

1: at line 1, in Alt:
idl = ws control_section metadata_section shape_section
^

2: at line 1, in Alt:
idl = ws control_section metadata_section shape_section
^

3: at line 1, in Many1:
idl = ws control_section metadata_section shape_section
^

Still, this is a bad error message and I understand why you thought it is related to newline. I do not have much time to work on this library currently, but do you mind if I include your test as a unit test? I think that I want to change two things in the future: 1) first accepting - in non-terminals and then yielding a better error message and 2) reworking how errors are displayed altogether. This is a painpoint, because I have not fully understood how Nom works here :-)

Thank you for the kind words, btw!