Trait concordium_std::marker::Sync 1.0.0[−][src]
pub unsafe auto trait Sync { }
Expand description
Types for which it is safe to share references between threads.
This trait is automatically implemented when the compiler determines it’s appropriate.
The precise definition is: a type T
is Sync
if and only if &T
is
Send
. In other words, if there is no possibility of
undefined behavior (including data races) when passing
&T
references between threads.
As one would expect, primitive types like u8
and f64
are all Sync
, and so are simple aggregate types containing them,
like tuples, structs and enums. More examples of basic Sync
types include “immutable” types like &T
, and those with simple
inherited mutability, such as Box<T>
, Vec<T>
and
most other collection types. (Generic parameters need to be Sync
for their container to be Sync
.)
A somewhat surprising consequence of the definition is that &mut T
is Sync
(if T
is Sync
) even though it seems like that might
provide unsynchronized mutation. The trick is that a mutable
reference behind a shared reference (that is, & &mut T
)
becomes read-only, as if it were a & &T
. Hence there is no risk
of a data race.
Types that are not Sync
are those that have “interior
mutability” in a non-thread-safe form, such as Cell
and RefCell
. These types allow for mutation of
their contents even through an immutable, shared reference. For
example the set
method on Cell<T>
takes &self
, so it requires
only a shared reference &Cell<T>
. The method performs no
synchronization, thus Cell
cannot be Sync
.
Another example of a non-Sync
type is the reference-counting
pointer Rc
. Given any reference &Rc<T>
, you can clone
a new Rc<T>
, modifying the reference counts in a non-atomic way.
For cases when one does need thread-safe interior mutability,
Rust provides atomic data types, as well as explicit locking via
sync::Mutex
and sync::RwLock
. These types
ensure that any mutation cannot cause data races, hence the types
are Sync
. Likewise, sync::Arc
provides a thread-safe
analogue of Rc
.
Any types with interior mutability must also use the
cell::UnsafeCell
wrapper around the value(s) which
can be mutated through a shared reference. Failing to doing this is
undefined behavior. For example, transmute
-ing
from &T
to &mut T
is invalid.
See the Nomicon for more details about Sync
.
Implementations on Foreign Types
impl Sync for Once
[src]
impl<T> !Sync for Receiver<T>
[src]
impl<T> Sync for JoinHandle<T>
[src]
impl<'_, T> Sync for MutexGuard<'_, T> where
T: Sync + ?Sized,
[src]
T: Sync + ?Sized,
impl<T> Sync for SyncOnceCell<T> where
T: Sync + Send,
[src]
T: Sync + Send,
impl<'_, T> Sync for RwLockWriteGuard<'_, T> where
T: Sync + ?Sized,
[src]
T: Sync + ?Sized,
impl !Sync for ArgsOs
[src]
impl<'_, T> Sync for RwLockReadGuard<'_, T> where
T: Sync + ?Sized,
[src]
T: Sync + ?Sized,
impl<T> Sync for Key<T>
[src]
impl<T, F> Sync for SyncLazy<T, F> where
F: Send,
SyncOnceCell<T>: Sync,
[src]
F: Send,
SyncOnceCell<T>: Sync,
impl<T> !Sync for Sender<T>
[src]
impl<'a> Sync for IoSliceMut<'a>
[src]
impl<T> Sync for RwLock<T> where
T: Send + Sync + ?Sized,
[src]
T: Send + Sync + ?Sized,
impl<'a> Sync for IoSlice<'a>
[src]
impl !Sync for Args
[src]
impl<T> Sync for Mutex<T> where
T: Send + ?Sized,
[src]
T: Send + ?Sized,
impl<T> !Sync for UnsafeCell<T> where
T: ?Sized,
[src]
T: ?Sized,
impl<Dyn> Sync for DynMetadata<Dyn> where
Dyn: ?Sized,
[src]
Dyn: ?Sized,
impl Sync for AtomicUsize
[src]
impl<'_, T> Sync for Iter<'_, T> where
T: Sync,
[src]
T: Sync,
impl Sync for AtomicU64
[src]
impl Sync for AtomicIsize
[src]
impl<T> !Sync for *const T where
T: ?Sized,
[src]
T: ?Sized,
impl Sync for AtomicI32
[src]
impl<T> !Sync for *mut T where
T: ?Sized,
[src]
T: ?Sized,
impl Sync for AtomicU8
[src]
impl<T> Sync for Empty<T>
[src]
impl Sync for AtomicBool
[src]
impl Sync for AtomicI16
[src]
impl Sync for AtomicI8
[src]
impl Sync for Waker
[src]
impl<T> !Sync for RefCell<T> where
T: ?Sized,
[src]
T: ?Sized,
impl<T> Sync for AtomicPtr<T>
[src]
impl Sync for AtomicI64
[src]
impl Sync for AtomicU16
[src]
impl<T> !Sync for Cell<T> where
T: ?Sized,
[src]
T: ?Sized,
impl<'_, T> Sync for IterMut<'_, T> where
T: Sync,
[src]
T: Sync,
impl Sync for AtomicU32
[src]
impl<T> !Sync for NonNull<T> where
T: ?Sized,
[src]
T: ?Sized,
NonNull
pointers are not Sync
because the data they reference may be aliased.
impl<'_> Sync for Drain<'_>
[src]
impl<T> Sync for Weak<T> where
T: Sync + Send + ?Sized,
[src]
T: Sync + Send + ?Sized,
impl<T> !Sync for Rc<T> where
T: ?Sized,
[src]
T: ?Sized,
impl<T, A> Sync for IntoIter<T, A> where
T: Sync,
A: Allocator,
[src]
T: Sync,
A: Allocator,
impl<'_, T, A> Sync for Drain<'_, T, A> where
T: Sync,
A: Sync + Allocator,
[src]
T: Sync,
A: Sync + Allocator,
impl<T> !Sync for Weak<T> where
T: ?Sized,
[src]
T: ?Sized,
impl<T> Sync for Arc<T> where
T: Sync + Send + ?Sized,
[src]
T: Sync + Send + ?Sized,
impl<'a> Sync for WeeAlloc<'a>
[src]
impl Sync for isize
impl<T> Sync for [T] where
T: Sync,
T: Sync,
impl Sync for [u8]
impl Sync for char
impl Sync for u128
impl Sync for u16
impl Sync for i128
impl Sync for i16
impl Sync for str
impl Sync for f64
impl Sync for u64
impl Sync for u8
impl Sync for i64
impl Sync for i8
impl<T, const N: usize> Sync for [T; N] where
T: Sync,
T: Sync,
impl Sync for bool
impl Sync for f32
impl Sync for u32
impl Sync for usize
impl Sync for i32
Loading content...Implementors
impl<'_, T> Sync for concordium_std::collections::linked_list::Cursor<'_, T> where
T: Sync,
[src]
T: Sync,
impl<'_, T> Sync for CursorMut<'_, T> where
T: Sync,
[src]
T: Sync,
impl<'_, T> Sync for concordium_std::collections::linked_list::Iter<'_, T> where
T: Sync,
[src]
T: Sync,
impl<'_, T> Sync for concordium_std::collections::linked_list::IterMut<'_, T> where
T: Sync,
[src]
T: Sync,
impl<'_, T> Sync for concordium_std::collections::vec_deque::Drain<'_, T> where
T: Sync,
1.6.0[src]
T: Sync,
impl<'_, T> Sync for concordium_std::collections::vec_deque::IterMut<'_, T> where
T: Sync,
[src]
T: Sync,
impl<T> Sync for LinkedList<T> where
T: Sync,
[src]
T: Sync,
Auto implementors
impl Sync for TryReserveError
impl Sync for Infallible
impl Sync for Address
impl Sync for AmountParseError
impl Sync for LogError
impl Sync for NewContractNameError
impl Sync for NewReceiveNameError
impl Sync for ParseDurationError
impl Sync for SeekFrom
impl Sync for FpCategory
impl Sync for IntErrorKind
impl Sync for Fields
impl Sync for SizeLength
impl Sync for Type
impl Sync for ActionsTree
impl Sync for ContractStateError
impl Sync for DefaultHasher
impl Sync for RandomState
impl Sync for NonZeroI8
impl Sync for NonZeroI16
impl Sync for NonZeroI32
impl Sync for NonZeroI64
impl Sync for NonZeroI128
impl Sync for NonZeroIsize
impl Sync for NonZeroU8
impl Sync for NonZeroU16
impl Sync for NonZeroU32
impl Sync for NonZeroU64
impl Sync for NonZeroU128
impl Sync for NonZeroUsize
impl Sync for ParseFloatError
impl Sync for ParseIntError
impl Sync for TryFromIntError
impl Sync for Contract
impl Sync for Module
impl Sync for AccountAddress
impl Sync for Action
impl Sync for Amount
impl Sync for AttributeTag
impl Sync for AttributesCursor
impl Sync for ChainMetadata
impl Sync for ContractAddress
impl Sync for ContractState
impl Sync for Duration
impl Sync for Logger
impl Sync for OwnedContractName
impl Sync for OwnedReceiveName
impl Sync for Parameter
impl Sync for ParseError
impl Sync for PoliciesIterator
impl Sync for Reject
impl Sync for String
impl Sync for Timestamp
impl Sync for ChainMetaTest
impl Sync for LogRecorder
impl Sync for TestPolicy
impl Sync for PhantomPinned
impl<'a> Sync for ContractName<'a>
impl<'a> Sync for ReceiveName<'a>
impl<'a, C> Sync for ContextTest<'a, C> where
C: Sync,
C: Sync,
impl<'a, K> Sync for concordium_std::collections::hash_set::Drain<'a, K> where
K: Sync,
K: Sync,
impl<'a, K> Sync for concordium_std::collections::hash_set::Iter<'a, K> where
K: Sync,
K: Sync,
impl<'a, K, F> Sync for concordium_std::collections::hash_set::DrainFilter<'a, K, F> where
F: Sync,
K: Sync,
F: Sync,
K: Sync,
impl<'a, K, V> Sync for concordium_std::collections::btree_map::Entry<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::hash_map::Entry<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::btree_map::Iter<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::btree_map::IterMut<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::btree_map::Keys<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::btree_map::OccupiedEntry<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::btree_map::OccupiedError<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::btree_map::Range<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for RangeMut<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::btree_map::VacantEntry<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::btree_map::Values<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::btree_map::ValuesMut<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::hash_map::Drain<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::hash_map::Iter<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::hash_map::IterMut<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::hash_map::Keys<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::hash_map::OccupiedEntry<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::hash_map::OccupiedError<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::hash_map::VacantEntry<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::hash_map::Values<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for concordium_std::collections::hash_map::ValuesMut<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V, F> Sync for concordium_std::collections::btree_map::DrainFilter<'a, K, V, F> where
F: Sync,
K: Sync,
V: Sync,
F: Sync,
K: Sync,
V: Sync,
impl<'a, K, V, F> Sync for concordium_std::collections::hash_map::DrainFilter<'a, K, V, F> where
F: Sync,
K: Sync,
V: Sync,
F: Sync,
K: Sync,
V: Sync,
impl<'a, K, V, S> Sync for RawEntryMut<'a, K, V, S> where
K: Sync,
S: Sync,
V: Sync,
K: Sync,
S: Sync,
V: Sync,
impl<'a, K, V, S> Sync for RawEntryBuilder<'a, K, V, S> where
K: Sync,
S: Sync,
V: Sync,
K: Sync,
S: Sync,
V: Sync,
impl<'a, K, V, S> Sync for RawEntryBuilderMut<'a, K, V, S> where
K: Sync,
S: Sync,
V: Sync,
K: Sync,
S: Sync,
V: Sync,
impl<'a, K, V, S> Sync for RawOccupiedEntryMut<'a, K, V, S> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V, S> Sync for RawVacantEntryMut<'a, K, V, S> where
K: Sync,
S: Sync,
V: Sync,
K: Sync,
S: Sync,
V: Sync,
impl<'a, T> Sync for concordium_std::collections::binary_heap::Drain<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for DrainSorted<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for concordium_std::collections::binary_heap::Iter<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for PeekMut<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for concordium_std::collections::btree_set::Difference<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for concordium_std::collections::btree_set::Intersection<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for concordium_std::collections::btree_set::Iter<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for concordium_std::collections::btree_set::Range<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for concordium_std::collections::btree_set::SymmetricDifference<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for concordium_std::collections::btree_set::Union<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for concordium_std::collections::vec_deque::Iter<'a, T> where
T: Sync,
T: Sync,
impl<'a, T, F> !Sync for concordium_std::collections::linked_list::DrainFilter<'a, T, F>
impl<'a, T, F> Sync for concordium_std::collections::btree_set::DrainFilter<'a, T, F> where
F: Sync,
T: Sync,
F: Sync,
T: Sync,
impl<'a, T, S> Sync for concordium_std::collections::hash_set::Difference<'a, T, S> where
S: Sync,
T: Sync,
S: Sync,
T: Sync,
impl<'a, T, S> Sync for concordium_std::collections::hash_set::Intersection<'a, T, S> where
S: Sync,
T: Sync,
S: Sync,
T: Sync,
impl<'a, T, S> Sync for concordium_std::collections::hash_set::SymmetricDifference<'a, T, S> where
S: Sync,
T: Sync,
S: Sync,
T: Sync,
impl<'a, T, S> Sync for concordium_std::collections::hash_set::Union<'a, T, S> where
S: Sync,
T: Sync,
S: Sync,
T: Sync,
impl<Attributes> Sync for Policy<Attributes> where
Attributes: Sync,
Attributes: Sync,
impl<K> Sync for concordium_std::collections::hash_set::IntoIter<K> where
K: Sync,
K: Sync,
impl<K, V> Sync for concordium_std::collections::btree_map::IntoIter<K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<K, V> Sync for concordium_std::collections::btree_map::IntoKeys<K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<K, V> Sync for concordium_std::collections::btree_map::IntoValues<K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<K, V> Sync for concordium_std::collections::hash_map::IntoIter<K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<K, V> Sync for concordium_std::collections::hash_map::IntoKeys<K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<K, V> Sync for concordium_std::collections::hash_map::IntoValues<K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<K, V> Sync for BTreeMap<K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<K, V, S> Sync for HashMap<K, V, S> where
K: Sync,
S: Sync,
V: Sync,
K: Sync,
S: Sync,
V: Sync,
impl<T> Sync for Bound<T> where
T: Sync,
T: Sync,
impl<T> Sync for concordium_std::collections::binary_heap::IntoIter<T> where
T: Sync,
T: Sync,
impl<T> Sync for IntoIterSorted<T> where
T: Sync,
T: Sync,
impl<T> Sync for concordium_std::collections::btree_set::IntoIter<T> where
T: Sync,
T: Sync,
impl<T> Sync for concordium_std::collections::linked_list::IntoIter<T> where
T: Sync,
T: Sync,
impl<T> Sync for BTreeSet<T> where
T: Sync,
T: Sync,
impl<T> Sync for BinaryHeap<T> where
T: Sync,
T: Sync,
impl<T> Sync for VecDeque<T> where
T: Sync,
T: Sync,
impl<T> Sync for concordium_std::collections::vec_deque::IntoIter<T> where
T: Sync,
T: Sync,
impl<T> Sync for Discriminant<T>
impl<T> Sync for Wrapping<T> where
T: Sync,
T: Sync,
impl<T> Sync for concordium_std::Cursor<T> where
T: Sync,
T: Sync,
impl<T> Sync for ContractStateTest<T> where
T: Sync,
T: Sync,
impl<T> Sync for MaybeUninit<T> where
T: Sync,
T: Sync,
impl<T, A> Sync for Vec<T, A> where
A: Sync,
T: Sync,
A: Sync,
T: Sync,
impl<T, S> Sync for HashSet<T, S> where
S: Sync,
T: Sync,
S: Sync,
T: Sync,
impl<T: ?Sized> Sync for ManuallyDrop<T> where
T: Sync,
T: Sync,
impl<T: ?Sized> Sync for PhantomData<T> where
T: Sync,
T: Sync,