Clap show generated description

---

examples/clap/show-generated-description/Cargo.toml

[package]
name = "show-generated-description"
version = "0.1.0"
edition = "2021"
description = "Description in Cargo.toml"

[dependencies]
clap = { version = "4.5.7", features = ["derive"] }

examples/clap/show-generated-description/src/main.rs

use clap::Parser;
use std::time::{SystemTime, UNIX_EPOCH};

#[derive(Parser)]
#[command(about = get_about())]
struct Cli {}

fn main() {
    let _args = Cli::parse();
    println!("Use the --help flag");
}

fn get_about() -> String {
    let start = SystemTime::now();
    let since_the_epoch = start
        .duration_since(UNIX_EPOCH)
        .expect("Time went backwards");
    format!(
        "The description generated at {}",
        since_the_epoch.as_nanos()
    )
}