gecko-dev/third_party/rust/clap/examples/escaped-positional.rs

use clap::{arg, command, value_parser, ArgAction};

fn main() {
    let matches = command!() // requires `cargo` feature
        .arg(arg!(eff: -f).action(ArgAction::SetTrue))
        .arg(arg!(pea: -p <PEAR>).value_parser(value_parser!(String)))
        .arg(
            // Indicates that `slop` is only accessible after `--`.
            arg!(slop: [SLOP])
                .num_args(1..)
                .last(true)
                .value_parser(value_parser!(String)),
        )
        .get_matches();

    // This is what will happen with `myprog -f -p=bob -- sloppy slop slop`...

    // -f used: true
    println!("-f used: {:?}", matches.get_flag("eff"));
    // -p's value: Some("bob")
    println!("-p's value: {:?}", matches.get_one::<String>("pea"));
    // 'slops' values: Some(["sloppy", "slop", "slop"])
    println!(
        "'slops' values: {:?}",
        matches
            .get_many::<String>("slop")
            .map(|vals| vals.collect::<Vec<_>>())
            .unwrap_or_default()
    );

    // Continued program logic goes here...
}