gistfile1.rs

// should recognize:
// input-node name=foo dim=12
// i want to assume both are here, but not necessarily in this order
// i have similar case with more numrous foo=bar cases 

fn parse_input_node_line(i: &str) -> IResult<&str, (String, usize)> {
    use crate::parser::spaced;
    use std::cell::Cell;
    let name: Cell<Option<String>> = Cell::new(None);
    let dim: Cell<Option<usize>> = Cell::new(None);
    let (i, _) = tag("input-node")(i)?;
    let (i, _) = many1(spaced(alt((
        map(preceded(tag("name="), identifier), |n| {
            name.set(Some(n.to_string()));
        }),
        map(preceded(tag("dim="), digit1), |n: &str| {
            dim.set(Some(n.parse().unwrap()));
        }),
    ))))(i)?;
    match (name.into_inner(), dim.into_inner()) {
        (Some(name), Some(dim)) => Ok((i, (name, dim))),
        (None, _) => panic!("expect name"),
        (_, None) => panic!("expect dim"),
    }
}