1use clap::{arg, command, value_parser};
2
3fn main() {
4 let matches = command!() // requires `cargo` feature
5 .arg(
6 arg!(<PORT>)
7 .help("Network port to use")
8 .value_parser(value_parser!(u16).range(1..)),
9 )
10 .get_matches();
11
12 // Note, it's safe to call unwrap() because the arg is required
13 let port: u16 = *matches
14 .get_one::<u16>("PORT")
15 .expect("'PORT' is required and parsing will fail if its missing");
16 println!("PORT = {port}");
17}
18