1 //! How to require presence of at least N values, 2 //! like `val1 val2 ... valN ... valM`. 3 4 use structopt::StructOpt; 5 6 #[derive(StructOpt, Debug)] 7 struct Opt { 8 #[structopt(required = true, min_values = 2)] 9 foos: Vec<String>, 10 } 11 main()12fn main() { 13 let opt = Opt::from_args(); 14 println!("{:?}", opt); 15 } 16