+//!
+//! Unbounded receive loop:
+//!
+//! ```
+//! use std::sync::mpsc::sync_channel;
+//! use std::thread;
+//!
+//! let (tx, rx) = sync_channel(3);
+//!
+//! for _ in 0..3 {
+//! // It would be the same without thread and clone here
+//! // since there will still be one `tx` left.
+//! let tx = tx.clone();
+//! // cloned tx dropped within thread
+//! thread::spawn(move || tx.send("ok").unwrap());
+//! }
+//!
+//! // Drop the last sender to stop `rx` waiting for message.
+//! // The program will not complete if we comment this out.
+//! // **All** `tx` needs to be dropped for `rx` to have `Err`.
+//! drop(tx);
+//!
+//! // Unbounded receiver waiting for all senders to complete.
+//! while let Ok(msg) = rx.recv() {
+//! println!("{}", msg);
+//! }
+//!
+//! println!("completed");
+//! ```