use clap::{arg, Args as _, Command, FromArgMatches as _, Parser}; #[derive(Parser, Debug)] struct DerivedArgs { #[clap(short, long, action)] derived: bool, } fn main() { let cli = Command::new("CLI").arg(arg!(-b - -built).action(clap::ArgAction::SetTrue)); // Augment built args with derived args let cli = DerivedArgs::augment_args(cli); let matches = cli.get_matches(); println!( "Value of built: {:?}", *matches.get_one::("built").unwrap() ); println!( "Value of derived via ArgMatches: {:?}", *matches.get_one::("derived").unwrap() ); // Since DerivedArgs implements FromArgMatches, we can extract it from the unstructured ArgMatches. // This is the main benefit of using derived arguments. let derived_matches = DerivedArgs::from_arg_matches(&matches) .map_err(|err| err.exit()) .unwrap(); println!("Value of derived: {:#?}", derived_matches); }