diff --git a/exercises/threads/threads3.rs b/exercises/threads/threads3.rs new file mode 100644 index 0000000..27e9908 --- /dev/null +++ b/exercises/threads/threads3.rs @@ -0,0 +1,64 @@ +// threads3.rs +// Execute `rustlings hint threads3` or use the `hint` watch subcommand for a hint. + +// I AM NOT DONE + +use std::sync::mpsc; +use std::sync::Arc; +use std::thread; +use std::time::Duration; + +struct Queue { + length: u32, + first_half: Vec, + second_half: Vec, +} + +impl Queue { + fn new() -> Self { + Queue { + length: 10, + first_half: vec![1, 2, 3, 4, 5], + second_half: vec![6, 7, 8, 9, 10], + } + } +} + +fn send_tx(q: Queue, tx: mpsc::Sender) -> () { + let qc = Arc::new(q); + let qc1 = qc.clone(); + let qc2 = qc.clone(); + + thread::spawn(move || { + for val in &qc1.first_half { + println!("sending {:?}", val); + tx.send(*val).unwrap(); + thread::sleep(Duration::from_secs(1)); + } + }); + + thread::spawn(move || { + for val in &qc2.second_half { + println!("sending {:?}", val); + tx.send(*val).unwrap(); + thread::sleep(Duration::from_secs(1)); + } + }); +} + +fn main() { + let (tx, rx) = mpsc::channel(); + let queue = Queue::new(); + let queue_length = queue.length; + + send_tx(queue, tx); + + let mut total_received: u32 = 0; + for received in rx { + println!("Got: {}", received); + total_received += 1; + } + + println!("total numbers received: {}", total_received); + assert_eq!(total_received, queue_length) +} diff --git a/info.toml b/info.toml index c239121..8871c15 100644 --- a/info.toml +++ b/info.toml @@ -918,6 +918,20 @@ If you've learned from the sample solutions, I encourage you to come back to this exercise and try it again in a few days to reinforce what you've learned :)""" +[[exercises]] +name = "threads3" +path = "exercises/threads/threads3.rs" +mode = "compile" +hint = """ +An alternate way to handle concurrency between threads is to use +a mpsc (multiple producer, single consumer) channel to communicate. +With both a sending end and a receiving end, it's possible to +send values in one thread and receieve them in another. +Multiple producers are possibile by using clone() to create a duplicate +of the original sending end. +See https://doc.rust-lang.org/book/ch16-02-message-passing.html for more info. +""" + # MACROS [[exercises]]