rust / intermediate
Snippet
Concurrent Programming with Channels
Rust's std::sync::mpsc channels enable safe thread communication. mpsc stands for multi-producer, single-consumer. The channel function creates a Sender and Receiver pair. send() transmits values and returns Result since the channel could be disconnected. recv() blocks until a message arrives. Multiple producers can send to the same channel, but only one consumer can receive. For multiple consumers, you would clone the receiver.
snippet.rs
rust
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use std::sync::mpsc;use std::thread;use std::time::Duration;fn main() {let (tx, rx) = mpsc::channel::<String>();let (tx2, rx2) = mpsc::channel::<u32>();let producer = thread::spawn(move || {for i in 1..=5 {let msg = format!("Message {}", i);tx.send(msg).unwrap();thread::sleep(Duration::from_millis(100));}});let consumer = thread::spawn(move || {for _ in 1..=5 {if let Ok(msg) = rx2.recv_timeout(Duration::from_secs(1)) {println!("Received number: {}", msg);}}});let _ = tx2.send(42);drop(tx2);producer.join().unwrap();consumer.join().unwrap();let (tx, rx) = mpsc::channel();tx.send("Direct message").unwrap();println!("Got: {}", rx.recv().unwrap());}
Breakdown
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let (tx, rx) = mpsc::channel::<String>();
Creates a typed channel; Sender (tx) and Receiver (rx)
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tx.send(msg).unwrap();
send returns Result because receiver might be dropped
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rx.recv_timeout(Duration::from_secs(1))
Waits up to 1 second for message; returns Timeout if none arrives
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drop(tx2);
Closing sender signals end-of-stream to receiver