rust-args-parser 2.0.0

use rust_args_parser as rapp;
use std::ffi::{OsStr, OsString};

#[derive(Default, Debug)]
struct Ctx {
    socket: Option<std::path::PathBuf>,
}

fn set_socket(v: &OsStr, c: &mut Ctx) {
    c.socket = Some(std::path::PathBuf::from(v));
}

fn non_empty(v: &OsStr) -> Result<(), &'static str> {
    if v.is_empty() {
        Err("empty value")
    } else {
        Ok(())
    }
}

fn main() {
    let env = rapp::Env::default();

    let root = rapp::CmdSpec::new("svc").help("Service tool with ENV/DEFAULT overlays").opt(
        rapp::OptSpec::value("socket", set_socket)
            .long("socket")
            .short('s')
            .metavar("PATH")
            .help("Control socket path")
            .env("SVC_SOCKET")
            .default("/run/svc.sock")
            .validator(non_empty),
    );

    let argv: Vec<OsString> = std::env::args_os().skip(1).collect();
    let mut ctx = Ctx::default();
    match rapp::parse(&env, &root, &argv, &mut ctx) {
        Err(rapp::Error::ExitMsg { code, message }) => {
            if let Some(msg) = message {
                print!("{msg}");
            }
            std::process::exit(code);
        }
        Err(e) => {
            eprintln!("error: {e}");
            std::process::exit(2);
        }
        Ok(_) => {}
    }

    eprintln!("socket = {:?}", ctx.socket);
}