pub unsafe auto trait Send { }🔬This is a nightly-only experimental API. (
prelude_future)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 Rcs 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 and the Sync trait for more details.
Implementors§
impl !Send for Args
impl !Send for ArgsOs
impl !Send for Arguments<'_>
impl !Send for LocalWaker
impl Send for core::ffi::c_str::Bytes<'_>
impl Send for ResumeTy
impl Send for rustc_std_workspace_std::string::Drain<'_>
impl Send for Waker
impl<'a> Send for IoSlice<'a>
impl<'a> Send for IoSliceMut<'a>
impl<Dyn> Send for DynMetadata<Dyn>where
Dyn: ?Sized,
impl<T> !Send for *const Twhere
T: ?Sized,
impl<T> !Send for *mut Twhere
T: ?Sized,
impl<T> !Send for NonNull<T>where
T: ?Sized,
NonNull pointers are not Send because the data they reference may be aliased.
impl<T> !Send for MappedMutexGuard<'_, T>where
T: ?Sized,
impl<T> !Send for MappedRwLockReadGuard<'_, T>where
T: ?Sized,
impl<T> !Send for MappedRwLockWriteGuard<'_, T>where
T: ?Sized,
impl<T> !Send for MutexGuard<'_, T>where
T: ?Sized,
A MutexGuard is not Send to maximize platform portablity.
On platforms that use POSIX threads (commonly referred to as pthreads) there is a requirement to
release mutex locks on the same thread they were acquired.
For this reason, MutexGuard must not implement Send to prevent it being dropped from
another thread.
impl<T> !Send for ReentrantLockGuard<'_, T>where
T: ?Sized,
impl<T> !Send for RwLockReadGuard<'_, T>where
T: ?Sized,
impl<T> !Send for RwLockWriteGuard<'_, T>where
T: ?Sized,
impl<T> Send for &T
impl<T> Send for ThinBox<T>
ThinBox<T> is Send if T is Send because the data is owned.
impl<T> Send for Cell<T>
impl<T> Send for RefCell<T>
impl<T> Send for rustc_std_workspace_std::collections::linked_list::Iter<'_, T>where
T: Sync,
impl<T> Send for rustc_std_workspace_std::collections::linked_list::IterMut<'_, T>where
T: Send,
impl<T> Send for NonZero<T>where
T: ZeroablePrimitive + Send,
impl<T> Send for Unique<T>
Unique pointers are Send if T is Send because the data they
reference is unaliased. Note that this aliasing invariant is
unenforced by the type system; the abstraction using the
Unique must enforce it.
impl<T> Send for ChunksExactMut<'_, T>where
T: Send,
impl<T> Send for ChunksMut<'_, T>where
T: Send,
impl<T> Send for rustc_std_workspace_std::slice::Iter<'_, T>where
T: Sync,
impl<T> Send for rustc_std_workspace_std::slice::IterMut<'_, T>where
T: Send,
impl<T> Send for RChunksExactMut<'_, T>where
T: Send,
impl<T> Send for RChunksMut<'_, T>where
T: Send,
impl<T> Send for AtomicPtr<T>
impl<T> Send for rustc_std_workspace_std::sync::mpmc::Receiver<T>where
T: Send,
impl<T> Send for rustc_std_workspace_std::sync::mpmc::Sender<T>where
T: Send,
impl<T> Send for rustc_std_workspace_std::sync::mpsc::Receiver<T>where
T: Send,
impl<T> Send for rustc_std_workspace_std::sync::mpsc::Sender<T>where
T: Send,
impl<T> Send for SyncSender<T>where
T: Send,
impl<T> Send for Mutex<T>
T must be Send for a Mutex to be Send because it is possible to acquire
the owned T from the Mutex via into_inner.