Module clap::_derive::_tutorial::chapter_4

Available on crate feature unstable-doc only.

Testing

clap reports most development errors as debug_assert!s. Rather than checking every subcommand, you should have a test that calls Command::debug_assert:

use clap::Parser;

#[derive(Parser)]
#[command(version, about, long_about = None)]
struct Cli {
    /// Network port to use
    port: u16,
}

fn main() {
    let cli = Cli::parse();

    println!("PORT = {}", cli.port);
}

#[test]
fn verify_cli() {
    use clap::CommandFactory;
    Cli::command().debug_assert()
}

Re-exports

• pub use super::chapter_3 as previous;
• pub use super::chapter_5 as next;
• pub use crate::_derive::_tutorial as table_of_contents;