diff options
| -rw-r--r-- | library/std/src/sync/once_lock.rs | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/library/std/src/sync/once_lock.rs b/library/std/src/sync/once_lock.rs index be615a5a8ef..0ae3cf4df36 100644 --- a/library/std/src/sync/once_lock.rs +++ b/library/std/src/sync/once_lock.rs @@ -634,6 +634,26 @@ impl<T> From<T> for OnceLock<T> { #[stable(feature = "once_cell", since = "1.70.0")] impl<T: PartialEq> PartialEq for OnceLock<T> { + /// Equality for two `OnceLock`s. + /// + /// Two `OnceLock`s are equal if they either both contain values and their + /// values are equal, or if neither contains a value. + /// + /// # Examples + /// + /// ``` + /// use std::sync::OnceLock; + /// + /// let five = OnceLock::new(); + /// five.set(5).unwrap(); + /// + /// let also_five = OnceLock::new(); + /// also_five.set(5).unwrap(); + /// + /// assert!(five == also_five); + /// + /// assert!(OnceLock::<u32>::new() == OnceLock::<u32>::new()); + /// ``` #[inline] fn eq(&self, other: &OnceLock<T>) -> bool { self.get() == other.get() |