Rollup merge of #110056 - chenyukang:yukang/fix-110045, r=workingjubilee

Fix the example in document for WaitTimeoutResult::timed_out

Fixes #110045

library/std/src/sync/condvar.rs

@@ -21,11 +21,11 @@ impl WaitTimeoutResult {
     ///
     /// # Examples
     ///
-    /// This example spawns a thread which will update the boolean value and
+    /// This example spawns a thread which will sleep 20 milliseconds before
-    /// then wait 100 milliseconds before notifying the condvar.
+    /// updating a boolean value and then notifying the condvar.
     ///
-    /// The main thread will wait with a timeout on the condvar and then leave
+    /// The main thread will wait with a 10 millisecond timeout on the condvar
-    /// once the boolean has been updated and notified.
+    /// and will leave the loop upon timeout.
     ///
     /// ```
     /// use std::sync::{Arc, Condvar, Mutex};
@@ -49,14 +49,12 @@ impl WaitTimeoutResult {
     ///
     /// // Wait for the thread to start up.
     /// let (lock, cvar) = &*pair;
-    /// let mut started = lock.lock().unwrap();
     /// loop {
     ///     // Let's put a timeout on the condvar's wait.
-    ///     let result = cvar.wait_timeout(started, Duration::from_millis(10)).unwrap();
+    ///     let result = cvar.wait_timeout(lock.lock().unwrap(), Duration::from_millis(10)).unwrap();
-    ///     // 10 milliseconds have passed, or maybe the value changed!
+    ///     // 10 milliseconds have passed.
-    ///     started = result.0;
+    ///     if result.1.timed_out() {
-    ///     if *started == true {
+    ///         // timed out now and we can leave.
-    ///         // We received the notification and the value has been updated, we can leave.
     ///         break
     ///     }
     /// }