pub unsafe auto trait Send { }
Expand description
Types that can be transferred across thread boundaries.
This trait is automatically implemented when the compiler determines it’s appropriate.
An example of a non-Send
type is the reference-counting pointer
rc::Rc
. If two threads attempt to clone Rc
s that point to the same
reference-counted value, they might try to update the reference count at the
same time, which is undefined behavior because Rc
doesn’t use atomic
operations. Its cousin sync::Arc
does use atomic operations (incurring
some overhead) and thus is Send
.
See the Nomicon for more details.
Implementations on Foreign Types
impl Send for Big32x40
impl Send for Big8x3
impl Send for Number
impl Send for Decoded
impl Send for FullDecoded
impl Send for Sign
impl<'a> Send for Part<'a>
impl<'a> Send for Formatted<'a>
impl Send for Argument
impl Send for FormatSpec
impl Send for Alignment
impl Send for Count
impl Send for Once
impl<'a> Send for IoSlice<'a>
impl !Send for ArgsOs
impl<'_, T> !Send for RwLockReadGuard<'_, T> where
T: ?Sized,
impl<T> Send for SyncSender<T> where
T: Send,
impl<T> Send for Receiver<T> where
T: Send,
impl<T> Send for Mutex<T> where
T: Send + ?Sized,
impl<'_, T> !Send for RwLockWriteGuard<'_, T> where
T: ?Sized,
impl<T> Send for Sender<T> where
T: Send,
impl<'_, T> !Send for MutexGuard<'_, T> where
T: ?Sized,
impl<T> Send for JoinHandle<T>
impl !Send for Args
impl<T> Send for RwLock<T> where
T: Send + ?Sized,
impl<T> Send for SyncOnceCell<T> where
T: Send,
impl<'a> Send for IoSliceMut<'a>
impl<'_, T> Send for &'_ T where
T: Sync + ?Sized,
impl<'_, T> Send for &'_ mut T where
T: Send + ?Sized,
impl<T> !Send for *mut T where
T: ?Sized,
impl<T> !Send for *const T where
T: ?Sized,
impl<T> Send for LinkedList<T> where
T: Send,
impl<T> !Send for Weak<T> where
T: ?Sized,
impl<'_, T> Send for Iter<'_, T> where
T: Sync,
impl<T> Send for Weak<T> where
T: Sync + Send + ?Sized,
impl<T> Send for Arc<T> where
T: Sync + Send + ?Sized,
impl<'_, T, A> Send for Drain<'_, T, A> where
T: Send,
A: Send + Allocator,
impl<'_, T> Send for CursorMut<'_, T> where
T: Send,
impl<'_, T> Send for Cursor<'_, T> where
T: Sync,
impl<'_, T> Send for IterMut<'_, T> where
T: Send,
impl<T, A> Send for IntoIter<T, A> where
T: Send,
A: Allocator + Send,
impl<'_, T> Send for IterMut<'_, T> where
T: Send,
impl<'_> Send for Drain<'_>
impl<'_, T, A> Send for Drain<'_, T, A> where
T: Send,
A: Allocator + Send,
impl<T> !Send for Rc<T> where
T: ?Sized,
impl<'_, K, V, S, A> Send for RawOccupiedEntryMut<'_, K, V, S, A> where
K: Send,
V: Send,
A: Send + Allocator + Clone,
impl<T> Send for Bucket<T>
impl<T, A> Send for RawTable<T, A> where
A: Allocator + Clone,
T: Send,
impl<'_, T, A> Send for RawDrain<'_, T, A> where
A: Allocator + Copy,
T: Send,
impl<'_, K, V> Send for IterMut<'_, K, V> where
K: Send,
V: Send,
impl<T, A> Send for RawIntoIter<T, A> where
A: Allocator + Clone,
T: Send,
impl<'_, K, V, S, A> Send for OccupiedEntry<'_, K, V, S, A> where
K: Send,
V: Send,
S: Send,
A: Send + Allocator + Clone,
Implementors
impl Send for Waker
impl<'_, T> Send for wasmtime_environ::__core::slice::Iter<'_, T> where
T: Sync,
impl<'_, T> Send for wasmtime_environ::__core::slice::IterMut<'_, T> where
T: Send,
impl<Dyn> Send for DynMetadata<Dyn> where
Dyn: ?Sized,
impl<T> !Send for NonNull<T> where
T: ?Sized,
NonNull
pointers are not Send
because the data they reference may be aliased.