commit	e2db2494ddd94b94f397e6799fbc250895307b84	[log] [tgz]
author	Matthew Maurer <mmaurer@google.com>	Fri Jun 05 16:18:19 2020 +0000
committer	Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>	Fri Jun 05 16:18:19 2020 +0000
tree	f7d078a929f919af60bc92ccd0044a5db21df4ee
parent	cbcb4bb236756dea82261909f47aee636829fc3f [diff]
parent	ca46d9e1932e11c2c1af92ad9ce9b4dde6baf072 [diff]

tree: f7d078a929f919af60bc92ccd0044a5db21df4ee

README.md

StructOpt

Parse command line arguments by defining a struct. It combines clap with custom derive.

Documentation

Find it on Docs.rs. You can also check the examples and the changelog.

Example

Add structopt to your dependencies of your Cargo.toml:

[dependencies]
structopt = "0.3"

And then, in your rust file:

use std::path::PathBuf;
use structopt::StructOpt;

/// A basic example
#[derive(StructOpt, Debug)]
#[structopt(name = "basic")]
struct Opt {
    // A flag, true if used in the command line. Note doc comment will
    // be used for the help message of the flag. The name of the
    // argument will be, by default, based on the name of the field.
    /// Activate debug mode
    #[structopt(short, long)]
    debug: bool,

    // The number of occurrences of the `v/verbose` flag
    /// Verbose mode (-v, -vv, -vvv, etc.)
    #[structopt(short, long, parse(from_occurrences))]
    verbose: u8,

    /// Set speed
    #[structopt(short, long, default_value = "42")]
    speed: f64,

    /// Output file
    #[structopt(short, long, parse(from_os_str))]
    output: PathBuf,

    // the long option will be translated by default to kebab case,
    // i.e. `--nb-cars`.
    /// Number of cars
    #[structopt(short = "c", long)]
    nb_cars: Option<i32>,

    /// admin_level to consider
    #[structopt(short, long)]
    level: Vec<String>,

    /// Files to process
    #[structopt(name = "FILE", parse(from_os_str))]
    files: Vec<PathBuf>,
}

fn main() {
    let opt = Opt::from_args();
    println!("{:#?}", opt);
}

Using this example:

$ ./basic
error: The following required arguments were not provided:
    --output <output>

USAGE:
    basic --output <output> --speed <speed>

For more information try --help
$ ./basic --help
basic 0.3.0
Guillaume Pinot <texitoi@texitoi.eu>, others
A basic example

USAGE:
    basic [FLAGS] [OPTIONS] --output <output> [--] [file]...

FLAGS:
    -d, --debug      Activate debug mode
    -h, --help       Prints help information
    -V, --version    Prints version information
    -v, --verbose    Verbose mode (-v, -vv, -vvv, etc.)

OPTIONS:
    -l, --level <level>...     admin_level to consider
    -c, --nb-cars <nb-cars>    Number of cars
    -o, --output <output>      Output file
    -s, --speed <speed>        Set speed [default: 42]

ARGS:
    <file>...    Files to process
$ ./basic -o foo.txt
Opt {
    debug: false,
    verbose: 0,
    speed: 42.0,
    output: "foo.txt",
    nb_cars: None,
    level: [],
    files: [],
}
$ ./basic -o foo.txt -dvvvs 1337 -l alice -l bob --nb-cars 4 bar.txt baz.txt
Opt {
    debug: true,
    verbose: 3,
    speed: 1337.0,
    output: "foo.txt",
    nb_cars: Some(
        4,
    ),
    level: [
        "alice",
        "bob",
    ],
    files: [
        "bar.txt",
        "baz.txt",
    ],
}

StructOpt rustc version policy

Minimum rustc version modification must be specified in the changelog and in the travis configuration.
Contributors can increment minimum rustc version without any justification if the new version is required by the latest version of one of StructOpt's dependencies (cargo update will not fail on StructOpt).
Contributors can increment minimum rustc version if the library user experience is improved.

License

Licensed under either of

Apache License, Version 2.0 (LICENSE-APACHE or https://www.apache.org/licenses/LICENSE-2.0)
MIT license (LICENSE-MIT or https://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.