Available on crate feature
unstable-doc
only.Expand description
Example: cargo subcommand (Derive API)
use clap::Parser;
#[derive(Parser)] // requires `derive` feature
#[clap(name = "cargo")]
#[clap(bin_name = "cargo")]
enum Cargo {
ExampleDerive(ExampleDerive),
}
#[derive(clap::Args)]
#[clap(author, version, about, long_about = None)]
struct ExampleDerive {
#[clap(long, value_parser)]
manifest_path: Option<std::path::PathBuf>,
}
fn main() {
let Cargo::ExampleDerive(args) = Cargo::parse();
println!("{:?}", args.manifest_path);
}
For more on creating a custom subcommand, see the cargo
book.
The crate clap-cargo
can help in
mimicking cargo’s interface.
The help looks like:
$ cargo-example-derive --help
cargo
USAGE:
cargo <SUBCOMMAND>
OPTIONS:
-h, --help Print help information
SUBCOMMANDS:
example-derive A simple to use, efficient, and full-featured Command Line Argument Parser
help Print this message or the help of the given subcommand(s)
$ cargo-example-derive example-derive --help
cargo-example-derive [..]
A simple to use, efficient, and full-featured Command Line Argument Parser
USAGE:
cargo example-derive [OPTIONS]
OPTIONS:
-h, --help Print help information
--manifest-path <MANIFEST_PATH>
-V, --version Print version information
Then to directly invoke the command, run:
$ cargo-example-derive example-derive
None
$ cargo-example-derive example-derive --manifest-path Cargo.toml
Some("Cargo.toml")