| //! Somewhat complex example of usage of structopt. |
| //! |
| //! Running this example with --help prints this message: |
| //! ----------------------------------------------------- |
| //! example 0.3.25 |
| //! An example of StructOpt usage |
| //! |
| //! USAGE: |
| //! example [FLAGS] [OPTIONS] <input> [--] [output] |
| //! |
| //! FLAGS: |
| //! -d, --debug Activate debug mode |
| //! -h, --help Prints help information |
| //! -V, --version Prints version information |
| //! |
| //! OPTIONS: |
| //! --log <log> Log file, stdout if no file, no logging if not present |
| //! --optv <optv>... |
| //! -s, --speed <speed> Set speed [default: 42] |
| //! |
| //! ARGS: |
| //! <input> Input file |
| //! <output> Output file, stdout if not present |
| //! ----------------------------------------------------- |
| |
| use structopt::StructOpt; |
| |
| #[derive(StructOpt, Debug)] |
| #[structopt(name = "example")] |
| /// An example of StructOpt usage. |
| struct Opt { |
| // A flag, true if used in the command line. |
| #[structopt(short, long)] |
| /// Activate debug mode |
| debug: bool, |
| |
| // An argument of type float, with a default value. |
| #[structopt(short, long, default_value = "42")] |
| /// Set speed |
| speed: f64, |
| |
| // Needed parameter, the first on the command line. |
| /// Input file |
| input: String, |
| |
| // An optional parameter, will be `None` if not present on the |
| // command line. |
| /// Output file, stdout if not present |
| output: Option<String>, |
| |
| // An optional parameter with optional value, will be `None` if |
| // not present on the command line, will be `Some(None)` if no |
| // argument is provided (i.e. `--log`) and will be |
| // `Some(Some(String))` if argument is provided (e.g. `--log |
| // log.txt`). |
| #[structopt(long)] |
| #[allow(clippy::option_option)] |
| /// Log file, stdout if no file, no logging if not present |
| log: Option<Option<String>>, |
| |
| // An optional list of values, will be `None` if not present on |
| // the command line, will be `Some(vec![])` if no argument is |
| // provided (i.e. `--optv`) and will be `Some(Vec<String>)` if |
| // argument list is provided (e.g. `--optv a b c`). |
| #[structopt(long)] |
| optv: Option<Vec<String>>, |
| |
| // Skipped option: it won't be parsed and will be filled with the |
| // default value for its type (in this case it'll be an empty string). |
| #[structopt(skip)] |
| skipped: String, |
| } |
| |
| fn main() { |
| let opt = Opt::from_args(); |
| println!("{:?}", opt); |
| } |