~irimi1/learning-rust

ref: 55f2f50bee1b7e2ab1c8ada879e7776b8e29654f learning-rust/projects/minigrep/src/main.rs -rw-r--r-- 1009 bytes
55f2f50bManuel Groß minigrep: Handle result that run() returns 2 years ago
                                                                                
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use std::env;
use std::error::Error;
use std::fs;
use std::process;

fn main() {
    let args: Vec<String> = env::args().collect();

    let config = Config::new(&args).unwrap_or_else(|err| {
        println!("Problem parsing arguments: {}", err);
        process::exit(1);
    });

    println!("Searching for {}", config.query);
    println!("In file {}", config.filename);

    if let Err(e) = run(config) {
        println!("Application error: {}", e);
        process::exit(1);
    }
}

fn run(config: Config) -> Result<(), Box<dyn Error>> {
    let contents = fs::read_to_string(config.filename)?;

    println!("With text:\n{}", contents);

    Ok(())
}

struct Config {
    query: String,
    filename: String,
}

impl Config {
    fn new(args: &[String]) -> Result<Config, &'static str> {
        if args.len() < 3 {
            return Err("not enough arguments");
        }
        let query = args[1].clone();
        let filename = args[2].clone();

        Ok(Config { query, filename })
    }
}