lelwel 0.10.4

Resilient LL(1) parser generator
Documentation 
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#![cfg(feature = "cli")]

use clap::{ArgAction, Command, arg, crate_name, crate_version, error::ErrorKind};

fn main() {
    let mut cmd = Command::new(crate_name!())
        .max_term_width(80)
        .version(crate_version!())
        .about("Generates recursive descent parsers for Rust using LL(1) grammars.")
        .arg(arg!(-c --check "Only check and don't change or write any files"))
        .arg(arg!(-f --format "Format the grammar file, exits with 1 if check mode is used and there were changes"))
        .arg(arg!(-g --graph "Output a graphviz file for the grammar"))
        .arg(arg!(-s --short "Use short diagnostics"))
        .arg(arg!(-v --verbose "Sets the level of verbosity").action(ArgAction::Count))
        .arg(
            arg!(-o --output <FILE> "Sets the output directory")
                .default_value(".")
                .required(false),
        )
        .arg(arg!(<INPUT> "Sets the input file to use"))
        .after_help("Report bugs to <https://github.com/0x2a-42/lelwel>.");

    let matches = cmd.get_matches_mut();

    let input = matches.get_one::<String>("INPUT").unwrap();
    let output = matches.get_one::<String>("output").unwrap();
    match lelwel::compile(
        input,
        output,
        matches.get_flag("check"),
        matches.get_flag("format"),
        matches.get_count("verbose"),
        matches.get_flag("graph"),
        matches.get_flag("short"),
    ) {
        Ok(success) => std::process::exit(if success { 0 } else { 1 }),
        Err(e) => cmd.error(ErrorKind::InvalidValue, format!("{e}")).exit(),
    }
}