vendor/clap/examples/tutorial_builder/04_02_parse.rs

   1 use clap::{arg, command, value_parser};
   2
   3 fn 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 }