Initial example Clap implementation has deprecation warnings - Command Line Applications In Rust

[ConnorJamesLow]

I am following the Command Line Applications In Rust tutorial using Rust 2021 edition. The book contains the following code:

#![allow(unused)]

use clap::Parser;

/// Search for a pattern in a file and display the lines that contain it.
#[derive(Parser)]
struct Cli {
    /// The pattern to look for
    pattern: String,
    /// The path to the file to read
    #[clap(parse(from_os_str))]
    path: std::path::PathBuf,
}

fn main() {
    let args = Cli::parse();
}

Which produces the following warnings:

Possible solutions:

• Update the book to use non-deprecated code.
• Else, if this was at one time stable, provide more specific versioning for Clap and Rust (adding the dependency according to the guide gave me clap v3.2.1).

[epage]

See also clap-rs/clap#3822

[epage]

Clap now hides the deprecations by default now.