1.0.0[−][src]Struct alloc_wg::sync::Arc
A thread-safe reference-counting pointer. 'Arc' stands for 'Atomically Reference Counted'.
The type Arc<T>
provides shared ownership of a value of type T
,
allocated in the heap. Invoking clone
on Arc
produces
a new Arc
instance, which points to the same allocation on the heap as the
source Arc
, while increasing a reference count. When the last Arc
pointer to a given allocation is destroyed, the value stored in that allocation (often
referred to as "inner value") is also dropped.
Shared references in Rust disallow mutation by default, and Arc
is no
exception: you cannot generally obtain a mutable reference to something
inside an Arc
. If you need to mutate through an Arc
, use
Mutex
, RwLock
, or one of the Atomic
types.
Thread Safety
Unlike Rc<T>
, Arc<T>
uses atomic operations for its reference
counting. This means that it is thread-safe. The disadvantage is that
atomic operations are more expensive than ordinary memory accesses. If you
are not sharing reference-counted allocations between threads, consider using
Rc<T>
for lower overhead. Rc<T>
is a safe default, because the
compiler will catch any attempt to send an Rc<T>
between threads.
However, a library might choose Arc<T>
in order to give library consumers
more flexibility.
Arc<T>
will implement Send
and Sync
as long as the T
implements
Send
and Sync
. Why can't you put a non-thread-safe type T
in an
Arc<T>
to make it thread-safe? This may be a bit counter-intuitive at
first: after all, isn't the point of Arc<T>
thread safety? The key is
this: Arc<T>
makes it thread safe to have multiple ownership of the same
data, but it doesn't add thread safety to its data. Consider
Arc<
RefCell<T>
>
. RefCell<T>
isn't Sync
, and if Arc<T>
was always
Send
, Arc<
RefCell<T>
>
would be as well. But then we'd have a problem:
RefCell<T>
is not thread safe; it keeps track of the borrowing count using
non-atomic operations.
In the end, this means that you may need to pair Arc<T>
with some sort of
std::sync
type, usually Mutex<T>
.
Breaking cycles with Weak
The downgrade
method can be used to create a non-owning
Weak
pointer. A Weak
pointer can be upgrade
d
to an Arc
, but this will return None
if the value stored in the allocation has
already been dropped. In other words, Weak
pointers do not keep the value
inside the allocation alive; however, they do keep the allocation
(the backing store for the value) alive.
A cycle between Arc
pointers will never be deallocated. For this reason,
Weak
is used to break cycles. For example, a tree could have
strong Arc
pointers from parent nodes to children, and Weak
pointers from children back to their parents.
Cloning references
Creating a new reference from an existing reference-counted pointer is done using the
Clone
trait implemented for Arc<T>
and Weak<T>
.
use std::sync::Arc; let foo = Arc::new(vec![1.0, 2.0, 3.0]); // The two syntaxes below are equivalent. let a = foo.clone(); let b = Arc::clone(&foo); // a, b, and foo are all Arcs that point to the same memory location
Deref
behavior
Arc<T>
automatically dereferences to T
(via the Deref
trait),
so you can call T
's methods on a value of type Arc<T>
. To avoid name
clashes with T
's methods, the methods of Arc<T>
itself are associated
functions, called using function-like syntax:
use std::sync::Arc; let my_arc = Arc::new(()); Arc::downgrade(&my_arc);
Weak<T>
does not auto-dereference to T
, because the inner value may have
already been dropped.
Examples
Sharing some immutable data between threads:
use std::sync::Arc; use std::thread; let five = Arc::new(5); for _ in 0..10 { let five = Arc::clone(&five); thread::spawn(move || { println!("{:?}", five); }); }
Sharing a mutable AtomicUsize
:
use std::sync::Arc; use std::sync::atomic::{AtomicUsize, Ordering}; use std::thread; let val = Arc::new(AtomicUsize::new(5)); for _ in 0..10 { let val = Arc::clone(&val); thread::spawn(move || { let v = val.fetch_add(1, Ordering::SeqCst); println!("{:?}", v); }); }
See the rc
documentation for more examples of reference
counting in general.
Implementations
impl<T> Arc<T>
[src]
pub fn new(data: T) -> Arc<T>
[src]
pub fn new_cyclic(data_fn: impl FnOnce(&Weak<T>) -> T) -> Arc<T>
[src]
arc_new_cyclic
)Constructs a new Arc<T>
using a weak reference to itself. Attempting
to upgrade the weak reference before this function returns will result
in a None
value. However, the weak reference may be cloned freely and
stored for use at a later time.
Examples
#![feature(arc_new_cyclic)] #![allow(dead_code)] use std::sync::{Arc, Weak}; struct Foo { me: Weak<Foo>, } let foo = Arc::new_cyclic(|me| Foo { me: me.clone(), });
pub fn new_uninit() -> Arc<MaybeUninit<T>>
[src]
new_uninit
)Constructs a new Arc
with uninitialized contents.
Examples
#![feature(new_uninit)] #![feature(get_mut_unchecked)] use std::sync::Arc; let mut five = Arc::<u32>::new_uninit(); let five = unsafe { // Deferred initialization: Arc::get_mut_unchecked(&mut five).as_mut_ptr().write(5); five.assume_init() }; assert_eq!(*five, 5)
pub fn new_zeroed() -> Arc<MaybeUninit<T>>
[src]
new_uninit
)Constructs a new Arc
with uninitialized contents, with the memory
being filled with 0
bytes.
See MaybeUninit::zeroed
for examples of correct and incorrect usage
of this method.
Examples
#![feature(new_uninit)] use std::sync::Arc; let zero = Arc::<u32>::new_zeroed(); let zero = unsafe { zero.assume_init() }; assert_eq!(*zero, 0)
pub fn pin(data: T) -> Pin<Arc<T>>
1.33.0[src]
Constructs a new Pin<Arc<T>>
. If T
does not implement Unpin
, then
data
will be pinned in memory and unable to be moved.
pub fn try_unwrap(this: Arc<T>) -> Result<T, Arc<T>>
1.4.0[src]
Returns the inner value, if the Arc
has exactly one strong reference.
Otherwise, an Err
is returned with the same Arc
that was
passed in.
This will succeed even if there are outstanding weak references.
Examples
use std::sync::Arc; let x = Arc::new(3); assert_eq!(Arc::try_unwrap(x), Ok(3)); let x = Arc::new(4); let _y = Arc::clone(&x); assert_eq!(*Arc::try_unwrap(x).unwrap_err(), 4);
impl<T> Arc<[T]>
[src]
pub fn new_uninit_slice(len: usize) -> Arc<[MaybeUninit<T>]>
[src]
new_uninit
)Constructs a new atomically reference-counted slice with uninitialized contents.
Examples
#![feature(new_uninit)] #![feature(get_mut_unchecked)] use std::sync::Arc; let mut values = Arc::<[u32]>::new_uninit_slice(3); let values = unsafe { // Deferred initialization: Arc::get_mut_unchecked(&mut values)[0].as_mut_ptr().write(1); Arc::get_mut_unchecked(&mut values)[1].as_mut_ptr().write(2); Arc::get_mut_unchecked(&mut values)[2].as_mut_ptr().write(3); values.assume_init() }; assert_eq!(*values, [1, 2, 3])
pub fn new_zeroed_slice(len: usize) -> Arc<[MaybeUninit<T>]>
[src]
new_uninit
)Constructs a new atomically reference-counted slice with uninitialized contents, with the memory being
filled with 0
bytes.
See MaybeUninit::zeroed
for examples of correct and
incorrect usage of this method.
Examples
#![feature(new_uninit)] use std::sync::Arc; let values = Arc::<[u32]>::new_zeroed_slice(3); let values = unsafe { values.assume_init() }; assert_eq!(*values, [0, 0, 0])
impl<T> Arc<MaybeUninit<T>>
[src]
pub unsafe fn assume_init(self) -> Arc<T>
[src]
new_uninit
)Converts to Arc<T>
.
Safety
As with MaybeUninit::assume_init
,
it is up to the caller to guarantee that the inner value
really is in an initialized state.
Calling this when the content is not yet fully initialized
causes immediate undefined behavior.
Examples
#![feature(new_uninit)] #![feature(get_mut_unchecked)] use std::sync::Arc; let mut five = Arc::<u32>::new_uninit(); let five = unsafe { // Deferred initialization: Arc::get_mut_unchecked(&mut five).as_mut_ptr().write(5); five.assume_init() }; assert_eq!(*five, 5)
impl<T> Arc<[MaybeUninit<T>]>
[src]
pub unsafe fn assume_init(self) -> Arc<[T]>
[src]
new_uninit
)Converts to Arc<[T]>
.
Safety
As with MaybeUninit::assume_init
,
it is up to the caller to guarantee that the inner value
really is in an initialized state.
Calling this when the content is not yet fully initialized
causes immediate undefined behavior.
Examples
#![feature(new_uninit)] #![feature(get_mut_unchecked)] use std::sync::Arc; let mut values = Arc::<[u32]>::new_uninit_slice(3); let values = unsafe { // Deferred initialization: Arc::get_mut_unchecked(&mut values)[0].as_mut_ptr().write(1); Arc::get_mut_unchecked(&mut values)[1].as_mut_ptr().write(2); Arc::get_mut_unchecked(&mut values)[2].as_mut_ptr().write(3); values.assume_init() }; assert_eq!(*values, [1, 2, 3])
impl<T> Arc<T> where
T: ?Sized,
[src]
T: ?Sized,
pub fn into_raw(this: Arc<T>) -> *const T
1.17.0[src]
Consumes the Arc
, returning the wrapped pointer.
To avoid a memory leak the pointer must be converted back to an Arc
using
Arc::from_raw
.
Examples
use std::sync::Arc; let x = Arc::new("hello".to_owned()); let x_ptr = Arc::into_raw(x); assert_eq!(unsafe { &*x_ptr }, "hello");
pub fn as_ptr(this: &Arc<T>) -> *const T
1.45.0[src]
Provides a raw pointer to the data.
The counts are not affected in any way and the Arc
is not consumed. The pointer is valid for
as long as there are strong counts in the Arc
.
Examples
use std::sync::Arc; let x = Arc::new("hello".to_owned()); let y = Arc::clone(&x); let x_ptr = Arc::as_ptr(&x); assert_eq!(x_ptr, Arc::as_ptr(&y)); assert_eq!(unsafe { &*x_ptr }, "hello");
pub unsafe fn from_raw(ptr: *const T) -> Arc<T>
1.17.0[src]
Constructs an Arc<T>
from a raw pointer.
The raw pointer must have been previously returned by a call to
Arc<U>::into_raw
where U
must have the same size and
alignment as T
. This is trivially true if U
is T
.
Note that if U
is not T
but has the same size and alignment, this is
basically like transmuting references of different types. See
mem::transmute
for more information on what
restrictions apply in this case.
The user of from_raw
has to make sure a specific value of T
is only
dropped once.
This function is unsafe because improper use may lead to memory unsafety,
even if the returned Arc<T>
is never accessed.
Examples
use std::sync::Arc; let x = Arc::new("hello".to_owned()); let x_ptr = Arc::into_raw(x); unsafe { // Convert back to an `Arc` to prevent leak. let x = Arc::from_raw(x_ptr); assert_eq!(&*x, "hello"); // Further calls to `Arc::from_raw(x_ptr)` would be memory-unsafe. } // The memory was freed when `x` went out of scope above, so `x_ptr` is now dangling!
pub fn downgrade(this: &Arc<T>) -> Weak<T>
1.4.0[src]
Creates a new Weak
pointer to this allocation.
Examples
use std::sync::Arc; let five = Arc::new(5); let weak_five = Arc::downgrade(&five);
pub fn weak_count(this: &Arc<T>) -> usize
1.15.0[src]
Gets the number of Weak
pointers to this allocation.
Safety
This method by itself is safe, but using it correctly requires extra care. Another thread can change the weak count at any time, including potentially between calling this method and acting on the result.
Examples
use std::sync::Arc; let five = Arc::new(5); let _weak_five = Arc::downgrade(&five); // This assertion is deterministic because we haven't shared // the `Arc` or `Weak` between threads. assert_eq!(1, Arc::weak_count(&five));
pub fn strong_count(this: &Arc<T>) -> usize
1.15.0[src]
Gets the number of strong (Arc
) pointers to this allocation.
Safety
This method by itself is safe, but using it correctly requires extra care. Another thread can change the strong count at any time, including potentially between calling this method and acting on the result.
Examples
use std::sync::Arc; let five = Arc::new(5); let _also_five = Arc::clone(&five); // This assertion is deterministic because we haven't shared // the `Arc` between threads. assert_eq!(2, Arc::strong_count(&five));
pub unsafe fn incr_strong_count(ptr: *const T)
[src]
arc_mutate_strong_count
)Increments the strong reference count on the Arc<T>
associated with the
provided pointer by one.
Safety
The pointer must have been obtained through Arc::into_raw
, and the
associated Arc
instance must be valid (i.e. the strong count must be at
least 1) for the duration of this method.
Examples
#![feature(arc_mutate_strong_count)] use std::sync::Arc; let five = Arc::new(5); unsafe { let ptr = Arc::into_raw(five); Arc::incr_strong_count(ptr); // This assertion is deterministic because we haven't shared // the `Arc` between threads. let five = Arc::from_raw(ptr); assert_eq!(2, Arc::strong_count(&five)); }
pub unsafe fn decr_strong_count(ptr: *const T)
[src]
arc_mutate_strong_count
)Decrements the strong reference count on the Arc<T>
associated with the
provided pointer by one.
Safety
The pointer must have been obtained through Arc::into_raw
, and the
associated Arc
instance must be valid (i.e. the strong count must be at
least 1) when invoking this method. This method can be used to release the final
Arc
and backing storage, but should not be called after the final Arc
has been
released.
Examples
#![feature(arc_mutate_strong_count)] use std::sync::Arc; let five = Arc::new(5); unsafe { let ptr = Arc::into_raw(five); Arc::incr_strong_count(ptr); // Those assertions are deterministic because we haven't shared // the `Arc` between threads. let five = Arc::from_raw(ptr); assert_eq!(2, Arc::strong_count(&five)); Arc::decr_strong_count(ptr); assert_eq!(1, Arc::strong_count(&five)); }
pub fn ptr_eq(this: &Arc<T>, other: &Arc<T>) -> bool
1.17.0[src]
impl<T> Arc<T> where
T: Clone,
[src]
T: Clone,
pub fn make_mut(this: &mut Arc<T>) -> &mut T
1.4.0[src]
Makes a mutable reference into the given Arc
.
If there are other Arc
or Weak
pointers to the same allocation,
then make_mut
will create a new allocation and invoke clone
on the inner value
to ensure unique ownership. This is also referred to as clone-on-write.
Note that this differs from the behavior of Rc::make_mut
which disassociates
any remaining Weak
pointers.
See also get_mut
, which will fail rather than cloning.
Examples
use std::sync::Arc; let mut data = Arc::new(5); *Arc::make_mut(&mut data) += 1; // Won't clone anything let mut other_data = Arc::clone(&data); // Won't clone inner data *Arc::make_mut(&mut data) += 1; // Clones inner data *Arc::make_mut(&mut data) += 1; // Won't clone anything *Arc::make_mut(&mut other_data) *= 2; // Won't clone anything // Now `data` and `other_data` point to different allocations. assert_eq!(*data, 8); assert_eq!(*other_data, 12);
impl<T> Arc<T> where
T: ?Sized,
[src]
T: ?Sized,
pub fn get_mut(this: &mut Arc<T>) -> Option<&mut T>
1.4.0[src]
Returns a mutable reference into the given Arc
, if there are
no other Arc
or Weak
pointers to the same allocation.
Returns None
otherwise, because it is not safe to
mutate a shared value.
See also make_mut
, which will clone
the inner value when there are other pointers.
Examples
use std::sync::Arc; let mut x = Arc::new(3); *Arc::get_mut(&mut x).unwrap() = 4; assert_eq!(*x, 4); let _y = Arc::clone(&x); assert!(Arc::get_mut(&mut x).is_none());
pub unsafe fn get_mut_unchecked(this: &mut Arc<T>) -> &mut T
[src]
get_mut_unchecked
)Returns a mutable reference into the given Arc
,
without any check.
See also get_mut
, which is safe and does appropriate checks.
Safety
Any other Arc
or Weak
pointers to the same allocation must not be dereferenced
for the duration of the returned borrow.
This is trivially the case if no such pointers exist,
for example immediately after Arc::new
.
Examples
#![feature(get_mut_unchecked)] use std::sync::Arc; let mut x = Arc::new(String::new()); unsafe { Arc::get_mut_unchecked(&mut x).push_str("foo") } assert_eq!(*x, "foo");
impl Arc<dyn Any + 'static + Sync + Send>
[src]
pub fn downcast<T>(self) -> Result<Arc<T>, Arc<dyn Any + 'static + Sync + Send>> where
T: Any + Send + Sync + 'static,
1.29.0[src]
T: Any + Send + Sync + 'static,
Attempt to downcast the Arc<dyn Any + Send + Sync>
to a concrete type.
Examples
use std::any::Any; use std::sync::Arc; fn print_if_string(value: Arc<dyn Any + Send + Sync>) { if let Ok(string) = value.downcast::<String>() { println!("String ({}): {}", string.len(), string); } } let my_string = "Hello World".to_string(); print_if_string(Arc::new(my_string)); print_if_string(Arc::new(0i8));
Trait Implementations
impl<T> AsRef<T> for Arc<T> where
T: ?Sized,
1.5.0[src]
T: ?Sized,
impl<T> Borrow<T> for Arc<T> where
T: ?Sized,
[src]
T: ?Sized,
impl<T> Clone for Arc<T> where
T: ?Sized,
[src]
T: ?Sized,
fn clone(&self) -> Arc<T>
[src]
Makes a clone of the Arc
pointer.
This creates another pointer to the same allocation, increasing the strong reference count.
Examples
use std::sync::Arc; let five = Arc::new(5); let _ = Arc::clone(&five);
fn clone_from(&mut self, source: &Self)
[src]
impl<T, U> CoerceUnsized<Arc<U>> for Arc<T> where
T: Unsize<U> + ?Sized,
U: ?Sized,
[src]
T: Unsize<U> + ?Sized,
U: ?Sized,
impl<T> Debug for Arc<T> where
T: Debug + ?Sized,
[src]
T: Debug + ?Sized,
impl<T> Default for Arc<T> where
T: Default,
[src]
T: Default,
fn default() -> Arc<T>
[src]
Creates a new Arc<T>
, with the Default
value for T
.
Examples
use std::sync::Arc; let x: Arc<i32> = Default::default(); assert_eq!(*x, 0);
impl<T> Deref for Arc<T> where
T: ?Sized,
[src]
T: ?Sized,
impl<T, U> DispatchFromDyn<Arc<U>> for Arc<T> where
T: Unsize<U> + ?Sized,
U: ?Sized,
[src]
T: Unsize<U> + ?Sized,
U: ?Sized,
impl<T> Display for Arc<T> where
T: Display + ?Sized,
[src]
T: Display + ?Sized,
impl<T> Drop for Arc<T> where
T: ?Sized,
[src]
T: ?Sized,
fn drop(&mut self)
[src]
Drops the Arc
.
This will decrement the strong reference count. If the strong reference
count reaches zero then the only other references (if any) are
Weak
, so we drop
the inner value.
Examples
use std::sync::Arc; struct Foo; impl Drop for Foo { fn drop(&mut self) { println!("dropped!"); } } let foo = Arc::new(Foo); let foo2 = Arc::clone(&foo); drop(foo); // Doesn't print anything drop(foo2); // Prints "dropped!"
impl<T> Eq for Arc<T> where
T: Eq + ?Sized,
[src]
T: Eq + ?Sized,
impl<'_, T> From<&'_ [T]> for Arc<[T]> where
T: Clone,
1.21.0[src]
T: Clone,
impl<'_> From<&'_ CStr> for Arc<CStr>
1.24.0[src]
impl<'_> From<&'_ OsStr> for Arc<OsStr>
1.24.0[src]
impl<'_> From<&'_ Path> for Arc<Path>
1.24.0[src]
fn from(s: &Path) -> Arc<Path>
[src]
Converts a Path
into an Arc
by copying the Path
data into a new Arc
buffer.
impl<'_> From<&'_ str> for Arc<str>
1.21.0[src]
impl<T> From<Box<T>> for Arc<T> where
T: ?Sized,
1.21.0[src]
T: ?Sized,
impl From<CString> for Arc<CStr>
1.24.0[src]
impl<'a, B> From<Cow<'a, B>> for Arc<B> where
B: ToOwned + ?Sized,
Arc<B>: From<&'a B>,
Arc<B>: From<<B as ToOwned>::Owned>,
1.45.0[src]
B: ToOwned + ?Sized,
Arc<B>: From<&'a B>,
Arc<B>: From<<B as ToOwned>::Owned>,
impl From<OsString> for Arc<OsStr>
1.24.0[src]
impl From<PathBuf> for Arc<Path>
1.24.0[src]
fn from(s: PathBuf) -> Arc<Path>
[src]
Converts a PathBuf
into an Arc
by moving the PathBuf
data into a new Arc
buffer.
impl From<String> for Arc<str>
1.21.0[src]
impl<T> From<T> for Arc<T>
1.6.0[src]
impl<T> From<Vec<T>> for Arc<[T]>
1.21.0[src]
impl<T> FromIterator<T> for Arc<[T]>
1.37.0[src]
fn from_iter<I>(iter: I) -> Arc<[T]> where
I: IntoIterator<Item = T>,
[src]
I: IntoIterator<Item = T>,
Takes each element in the Iterator
and collects it into an Arc<[T]>
.
Performance characteristics
The general case
In the general case, collecting into Arc<[T]>
is done by first
collecting into a Vec<T>
. That is, when writing the following:
let evens: Arc<[u8]> = (0..10).filter(|&x| x % 2 == 0).collect();
this behaves as if we wrote:
let evens: Arc<[u8]> = (0..10).filter(|&x| x % 2 == 0) .collect::<Vec<_>>() // The first set of allocations happens here. .into(); // A second allocation for `Arc<[T]>` happens here.
This will allocate as many times as needed for constructing the Vec<T>
and then it will allocate once for turning the Vec<T>
into the Arc<[T]>
.
Iterators of known length
When your Iterator
implements TrustedLen
and is of an exact size,
a single allocation will be made for the Arc<[T]>
. For example:
let evens: Arc<[u8]> = (0..10).collect(); // Just a single allocation happens here.
impl<T> Hash for Arc<T> where
T: Hash + ?Sized,
[src]
T: Hash + ?Sized,
fn hash<H>(&self, state: &mut H) where
H: Hasher,
[src]
H: Hasher,
fn hash_slice<H>(data: &[Self], state: &mut H) where
H: Hasher,
1.3.0[src]
H: Hasher,
impl<T> Ord for Arc<T> where
T: Ord + ?Sized,
[src]
T: Ord + ?Sized,
fn cmp(&self, other: &Arc<T>) -> Ordering
[src]
Comparison for two Arc
s.
The two are compared by calling cmp()
on their inner values.
Examples
use std::sync::Arc; use std::cmp::Ordering; let five = Arc::new(5); assert_eq!(Ordering::Less, five.cmp(&Arc::new(6)));
#[must_use]fn max(self, other: Self) -> Self
1.21.0[src]
#[must_use]fn min(self, other: Self) -> Self
1.21.0[src]
#[must_use]fn clamp(self, min: Self, max: Self) -> Self
[src]
impl<T> PartialEq<Arc<T>> for Arc<T> where
T: PartialEq<T> + ?Sized,
[src]
T: PartialEq<T> + ?Sized,
fn eq(&self, other: &Arc<T>) -> bool
[src]
Equality for two Arc
s.
Two Arc
s are equal if their inner values are equal, even if they are
stored in different allocation.
If T
also implements Eq
(implying reflexivity of equality),
two Arc
s that point to the same allocation are always equal.
Examples
use std::sync::Arc; let five = Arc::new(5); assert!(five == Arc::new(5));
fn ne(&self, other: &Arc<T>) -> bool
[src]
Inequality for two Arc
s.
Two Arc
s are unequal if their inner values are unequal.
If T
also implements Eq
(implying reflexivity of equality),
two Arc
s that point to the same value are never unequal.
Examples
use std::sync::Arc; let five = Arc::new(5); assert!(five != Arc::new(6));
impl<T> PartialOrd<Arc<T>> for Arc<T> where
T: PartialOrd<T> + ?Sized,
[src]
T: PartialOrd<T> + ?Sized,
fn partial_cmp(&self, other: &Arc<T>) -> Option<Ordering>
[src]
Partial comparison for two Arc
s.
The two are compared by calling partial_cmp()
on their inner values.
Examples
use std::sync::Arc; use std::cmp::Ordering; let five = Arc::new(5); assert_eq!(Some(Ordering::Less), five.partial_cmp(&Arc::new(6)));
fn lt(&self, other: &Arc<T>) -> bool
[src]
Less-than comparison for two Arc
s.
The two are compared by calling <
on their inner values.
Examples
use std::sync::Arc; let five = Arc::new(5); assert!(five < Arc::new(6));
fn le(&self, other: &Arc<T>) -> bool
[src]
'Less than or equal to' comparison for two Arc
s.
The two are compared by calling <=
on their inner values.
Examples
use std::sync::Arc; let five = Arc::new(5); assert!(five <= Arc::new(5));
fn gt(&self, other: &Arc<T>) -> bool
[src]
Greater-than comparison for two Arc
s.
The two are compared by calling >
on their inner values.
Examples
use std::sync::Arc; let five = Arc::new(5); assert!(five > Arc::new(4));
fn ge(&self, other: &Arc<T>) -> bool
[src]
'Greater than or equal to' comparison for two Arc
s.
The two are compared by calling >=
on their inner values.
Examples
use std::sync::Arc; let five = Arc::new(5); assert!(five >= Arc::new(5));
impl<T> Pointer for Arc<T> where
T: ?Sized,
[src]
T: ?Sized,
impl<T> Send for Arc<T> where
T: Send + Sync + ?Sized,
[src]
T: Send + Sync + ?Sized,
impl<T> Sync for Arc<T> where
T: Send + Sync + ?Sized,
[src]
T: Send + Sync + ?Sized,
impl<T, const N: usize> TryFrom<Arc<[T]>> for Arc<[T; N]>
1.43.0[src]
type Error = Arc<[T]>
The type returned in the event of a conversion error.
fn try_from(
boxed_slice: Arc<[T]>
) -> Result<Arc<[T; N]>, <Arc<[T; N]> as TryFrom<Arc<[T]>>>::Error>
[src]
boxed_slice: Arc<[T]>
) -> Result<Arc<[T; N]>, <Arc<[T; N]> as TryFrom<Arc<[T]>>>::Error>
impl<T> Unpin for Arc<T> where
T: ?Sized,
1.33.0[src]
T: ?Sized,
impl<T> UnwindSafe for Arc<T> where
T: RefUnwindSafe + ?Sized,
1.9.0[src]
T: RefUnwindSafe + ?Sized,
Auto Trait Implementations
impl<T: ?Sized> RefUnwindSafe for Arc<T> where
T: RefUnwindSafe,
T: RefUnwindSafe,
Blanket Implementations
impl<T> Any for T where
T: 'static + ?Sized,
[src]
T: 'static + ?Sized,
impl<T> Borrow<T> for T where
T: ?Sized,
[src]
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
[src]
T: ?Sized,
fn borrow_mut(&mut self) -> &mut T
[src]
impl<T> From<!> for T
[src]
impl<T> From<T> for T
[src]
impl<T, U> Into<U> for T where
U: From<T>,
[src]
U: From<T>,
impl<T> ToOwned for T where
T: Clone,
[src]
T: Clone,
type Owned = T
The resulting type after obtaining ownership.
fn to_owned(&self) -> T
[src]
fn clone_into(&self, target: &mut T)
[src]
impl<T> ToString for T where
T: Display + ?Sized,
[src]
T: Display + ?Sized,
impl<T, U> TryFrom<U> for T where
U: Into<T>,
[src]
U: Into<T>,
type Error = Infallible
The type returned in the event of a conversion error.
fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>
[src]
impl<T, U> TryInto<U> for T where
U: TryFrom<T>,
[src]
U: TryFrom<T>,