1 //! How to require presence of at least N values, 2 //! like `val1 val2 ... valN ... valM`. 3 //! 4 //! Running this example with --help prints this message: 5 //! ----------------------------------------------------- 6 //! structopt 0.3.25 7 //! 8 //! USAGE: 9 //! at_least_two <foos>... 10 //! 11 //! FLAGS: 12 //! -h, --help Prints help information 13 //! -V, --version Prints version information 14 //! 15 //! ARGS: 16 //! <foos>... 17 //! ----------------------------------------------------- 18 19 use structopt::StructOpt; 20 21 #[derive(StructOpt, Debug)] 22 struct Opt { 23 #[structopt(required = true, min_values = 2)] 24 foos: Vec<String>, 25 } 26 main()27fn main() { 28 let opt = Opt::from_args(); 29 println!("{:?}", opt); 30 } 31