Exercise solutions

Hi, this is a great tutorial!

As I am working through the book, I am trying the reader exercises — it would be great to have some solutions to refer to.

For example, Chapter 1.3 suggests one use a BufReader, so I have an attempt:

use std::fs::File;
use std::io::BufRead;
use std::io::BufReader;
use std::io::Read;

use clap::Parser;

#[derive(Parser)]
struct Cli {
    pattern: String,
    #[clap(parse(from_os_str))]
    path: std::path::PathBuf,
}

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

    println!(
        "You parsed pattern = {:?}, path = {:?}",
        &args.pattern, &args.path
    );

    let f = File::open(&args.path).expect("could not read file");
    let mut f = BufReader::new(f);

    for line in f.by_ref().lines() {
        if line.as_ref().unwrap().contains(&args.pattern) {
            println!("{}", line.as_ref().unwrap());
        }
    }
}

Now I'd like to see how to improve this.

Have I merely missed this somewhere in the book?

Start by reviewing the reader exercises in the book, including the Chapter 1.3 implementation draft linked in the issue and its BufReader example. Determine which exercises need reference solutions and how they should be presented. Done means the requested exercise solutions are available for readers to consult.