use clap::{App, AppSettings}; fn main() { let app = App::new(env!("CARGO_CRATE_NAME")) .setting(AppSettings::ArgRequiredElseHelp) .subcommand_value_name("APPLET") .subcommand_help_heading("APPLETS") .subcommand(App::new("hostname").about("show hostname part of FQDN")) .subcommand(App::new("dnsdomainname").about("show domain name part of FQDN")); let app = app.setting(AppSettings::Multicall); match app.get_matches().subcommand_name() { Some("hostname") => println!("www"), Some("dnsdomainname") => println!("example.com"), _ => unreachable!("parser should ensure only valid subcommand names are used"), } }