Rust연습❤️HashMap, Arc, Mutex, thread연습

main.rs

// Thanks: https://stackoverflow.com/a/53894298/665869
use std::collections::HashMap;
use std::sync::{Arc, Mutex};
use std::thread;

type Map = HashMap<String, String>;

fn handle_n_times(count: i32, arc_map: Arc<Mutex<Map>>) {
    for i in 0..count {
        let clone_arc = arc_map.clone();
        thread::spawn(move || {
            let mut map = clone_arc.lock().unwrap();
            map.insert(format!("key-{}", i), format!("value-{}", i));
        });
    }
}

fn print_map_items(arc_map: Arc<Mutex<Map>>) {
    let clone_arc = arc_map.clone();
    let map = clone_arc.lock().unwrap();
    for (k, v) in map.iter() {
        println!("k: {} v: {}", k, v);
    }
}

fn main() {
    let arc_map = Arc::new(Mutex::new(Map::new()));
    handle_n_times(5, arc_map.clone());

    // todo: join the threads above, wait them till finished

    print_map_items(arc_map.clone());
}

결과

cargo run

   Compiling rust_polyglot v0.1.0 (/Users/globalyoung/Documents/Project/Github/rust_project/rust_polyglot)
    Finished dev [unoptimized + debuginfo] target(s) in 2.27s
     Running `target/debug/rust_polyglot`
     
k: key-2 v: value-2
k: key-0 v: value-0
k: key-1 v: value-1

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https://youtu.be/ojKxus7EqKI

https://gist.github.com/mitnk/881ad1b8f58543dd76c007cac3f375a9

Lifetime with Thread (Mutex, Arc) in Rust

https://stackoverflow.com/questions/53892938/rust-lifetime-issue-with-threads/53894298#53894298

Rust Lifetime Issue with Threads

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