good-read-line.rs

use std::env;
use std::fs;

fn main() -> Result<(), std::io::Error> {
    let name = env::args().nth(1).expect("to pass an argument");

    // Version 1
    fs::read_to_string(&name)?
        .lines()
        .flat_map(|x| x.parse::<i32>())
        .for_each(|x| println!("{x:?}"));

    // Version 2, I kind of like passing func directly
    fs::read_to_string(&name)?
        .lines()
        .flat_map(str::parse::<i32>)
        .for_each(|x| println!("{x:?}"));

    Ok(())
}