Reddit Nom Help

Cargo.toml

[package]
name = "nom-test"
version = "0.1.0"
authors = ["Andrew <[email protected]>"]

[dependencies]
nom = "1.2.0"

lib.rs

#[macro_use]
extern crate nom;

use nom::{IResult, alphanumeric};

named!(pub atom_specials,
    alt!(
        tag!("(")
        | tag!(")")
        | tag!("{")
        | tag!(" ")
        | tag!("(")
        | tag!("a")
    )
);

pub fn atom_chars(bytes: &[u8]) -> IResult<&[u8], &[u8]> {
    cond_reduce!(bytes, !atom_specials(bytes).is_done(), chain!(
        alpha: peek!(alphanumeric) ~
        _____: take!(1) ,
        || { &alpha[..1] }
    ))
}

#[cfg(test)]
mod tests {
    use nom::{IResult};

    #[test]
    fn test_atom_specials() {
        let input = &b"()"[..];
        let output = vec![&b"("[..], &b")"[..]];

        let received = many1!(input, super::atom_specials);
        let expected: IResult<&[u8], Vec<&[u8]>> = IResult::Done(&b""[..], output);

        assert_eq!(received, expected);
    }

    #[test]
    fn test_atom_chars() {
        let input = &b"0Z"[..];
        let output = vec![&b"0"[..], &b"Z"[..]];

        let received = many1!(input, super::atom_chars);
        let expected: IResult<&[u8], Vec<&[u8]>> = IResult::Done(&b""[..], output);

        assert_eq!(received, expected);
    }
}