# 1.0.0[−][src]Struct core::sync::atomic::AtomicBool

    #[repr(C, align(1))]pub struct AtomicBool { /* fields omitted */ }

A boolean type which can be safely shared between threads.

This type has the same in-memory representation as a `bool`.

Note: This type is only available on platforms that support atomic loads and stores of `u8`.

## Implementations

### `impl AtomicBool`[src]

#### `pub const fn new(v: bool) -> AtomicBool`[src]

Creates a new `AtomicBool`.

# Examples

    use std::sync::atomic::AtomicBool;

    let atomic_true  = AtomicBool::new(true);
    let atomic_false = AtomicBool::new(false);

Run

#### `pub fn get_mut(&mut self) -> &mut bool` 1.15.0[src]

Returns a mutable reference to the underlying `bool`.

This is safe because the mutable reference guarantees that no other threads are concurrently accessing the atomic data.

# Examples

    use std::sync::atomic::{AtomicBool, Ordering};

    let mut some_bool = AtomicBool::new(true);
    assert_eq!(*some_bool.get_mut(), true);
    *some_bool.get_mut() = false;
    assert_eq!(some_bool.load(Ordering::SeqCst), false);

Run

#### `pub fn into_inner(self) -> bool` 1.15.0[src]

Consumes the atomic and returns the contained value.

This is safe because passing `self` by value guarantees that no other threads are concurrently accessing the atomic data.

# Examples

    use std::sync::atomic::AtomicBool;

    let some_bool = AtomicBool::new(true);
    assert_eq!(some_bool.into_inner(), true);

Run

#### `pub fn load(&self, order: Ordering) -> bool`[src]

Loads a value from the bool.

`load` takes an `Ordering` argument which describes the memory ordering of this operation. Possible values are `SeqCst`, `Acquire` and `Relaxed`.

# Panics

Panics if `order` is `Release` or `AcqRel`.

# Examples

    use std::sync::atomic::{AtomicBool, Ordering};

    let some_bool = AtomicBool::new(true);

    assert_eq!(some_bool.load(Ordering::Relaxed), true);

Run

#### `pub fn store(&self, val: bool, order: Ordering)`[src]

Stores a value into the bool.

`store` takes an `Ordering` argument which describes the memory ordering of this operation. Possible values are `SeqCst`, `Release` and `Relaxed`.

# Panics

Panics if `order` is `Acquire` or `AcqRel`.

# Examples

    use std::sync::atomic::{AtomicBool, Ordering};

    let some_bool = AtomicBool::new(true);

    some_bool.store(false, Ordering::Relaxed);
    assert_eq!(some_bool.load(Ordering::Relaxed), false);

Run

#### `pub fn swap(&self, val: bool, order: Ordering) -> bool`[src]

Stores a value into the bool, returning the previous value.

`swap` takes an `Ordering` argument which describes the memory ordering of this operation. All ordering modes are possible. Note that using `Acquire` makes the store part of this operation `Relaxed`, and using `Release` makes the load part `Relaxed`.

Note: This method is only available on platforms that support atomic operations on `u8`.

# Examples

    use std::sync::atomic::{AtomicBool, Ordering};

    let some_bool = AtomicBool::new(true);

    assert_eq!(some_bool.swap(false, Ordering::Relaxed), true);
    assert_eq!(some_bool.load(Ordering::Relaxed), false);

Run

#### `pub fn compare_and_swap(
&self,
current: bool,
new: bool,
order: Ordering
) -> bool`[src]

Stores a value into the `bool` if the current value is the same as the `current` value.

The return value is always the previous value. If it is equal to `current`, then the value was updated.

`compare_and_swap` also takes an `Ordering` argument which describes the memory ordering of this operation. Notice that even when using `AcqRel`, the operation might fail and hence just perform an `Acquire` load, but not have `Release` semantics. Using `Acquire` makes the store part of this operation `Relaxed` if it happens, and using `Release` makes the load part `Relaxed`.

Note: This method is only available on platforms that support atomic operations on `u8`.

# Examples

    use std::sync::atomic::{AtomicBool, Ordering};

    let some_bool = AtomicBool::new(true);

    assert_eq!(some_bool.compare_and_swap(true, false, Ordering::Relaxed), true);
    assert_eq!(some_bool.load(Ordering::Relaxed), false);

    assert_eq!(some_bool.compare_and_swap(true, true, Ordering::Relaxed), false);
    assert_eq!(some_bool.load(Ordering::Relaxed), false);

Run

#### `pub fn compare_exchange(
&self,
current: bool,
new: bool,
success: Ordering,
failure: Ordering
) -> Result<bool, bool>`1.10.0[src]

Stores a value into the `bool` if the current value is the same as the `current` value.

The return value is a result indicating whether the new value was written and containing the previous value. On success this value is guaranteed to be equal to `current`.

`compare_exchange` takes two `Ordering` arguments to describe the memory ordering of this operation. The first describes the required ordering if the operation succeeds while the second describes the required ordering when the operation fails. Using `Acquire` as success ordering makes the store part of this operation `Relaxed`, and using `Release` makes the successful load `Relaxed`. The failure ordering can only be `SeqCst`, `Acquire` or `Relaxed` and must be equivalent to or weaker than the success ordering.

Note: This method is only available on platforms that support atomic operations on `u8`.

# Examples

    use std::sync::atomic::{AtomicBool, Ordering};

    let some_bool = AtomicBool::new(true);

    assert_eq!(some_bool.compare_exchange(true,
                                          false,
                                          Ordering::Acquire,
                                          Ordering::Relaxed),
               Ok(true));
    assert_eq!(some_bool.load(Ordering::Relaxed), false);

    assert_eq!(some_bool.compare_exchange(true, true,
                                          Ordering::SeqCst,
                                          Ordering::Acquire),
               Err(false));
    assert_eq!(some_bool.load(Ordering::Relaxed), false);

Run

#### `pub fn compare_exchange_weak(
&self,
current: bool,
new: bool,
success: Ordering,
failure: Ordering
) -> Result<bool, bool>`1.10.0[src]

Stores a value into the `bool` if the current value is the same as the `current` value.

Unlike `compare_exchange`, this function is allowed to spuriously fail even when the comparison succeeds, which can result in more efficient code on some platforms. The return value is a result indicating whether the new value was written and containing the previous value.

`compare_exchange_weak` takes two `Ordering` arguments to describe the memory ordering of this operation. The first describes the required ordering if the operation succeeds while the second describes the required ordering when the operation fails. Using `Acquire` as success ordering makes the store part of this operation `Relaxed`, and using `Release` makes the successful load `Relaxed`. The failure ordering can only be `SeqCst`, `Acquire` or `Relaxed` and must be equivalent to or weaker than the success ordering.

Note: This method is only available on platforms that support atomic operations on `u8`.

# Examples

    use std::sync::atomic::{AtomicBool, Ordering};

    let val = AtomicBool::new(false);

    let new = true;
    let mut old = val.load(Ordering::Relaxed);
    loop {
        match val.compare_exchange_weak(old, new, Ordering::SeqCst, Ordering::Relaxed) {
            Ok(_) => break,
            Err(x) => old = x,
        }
    }

Run

#### `pub fn fetch_and(&self, val: bool, order: Ordering) -> bool`[src]

Logical "and" with a boolean value.

Performs a logical "and" operation on the current value and the argument `val`, and sets the new value to the result.

Returns the previous value.

`fetch_and` takes an `Ordering` argument which describes the memory ordering of this operation. All ordering modes are possible. Note that using `Acquire` makes the store part of this operation `Relaxed`, and using `Release` makes the load part `Relaxed`.

Note: This method is only available on platforms that support atomic operations on `u8`.

# Examples

    use std::sync::atomic::{AtomicBool, Ordering};

    let foo = AtomicBool::new(true);
    assert_eq!(foo.fetch_and(false, Ordering::SeqCst), true);
    assert_eq!(foo.load(Ordering::SeqCst), false);

    let foo = AtomicBool::new(true);
    assert_eq!(foo.fetch_and(true, Ordering::SeqCst), true);
    assert_eq!(foo.load(Ordering::SeqCst), true);

    let foo = AtomicBool::new(false);
    assert_eq!(foo.fetch_and(false, Ordering::SeqCst), false);
    assert_eq!(foo.load(Ordering::SeqCst), false);

Run

#### `pub fn fetch_nand(&self, val: bool, order: Ordering) -> bool`[src]

Logical "nand" with a boolean value.

Performs a logical "nand" operation on the current value and the argument `val`, and sets the new value to the result.

Returns the previous value.

`fetch_nand` takes an `Ordering` argument which describes the memory ordering of this operation. All ordering modes are possible. Note that using `Acquire` makes the store part of this operation `Relaxed`, and using `Release` makes the load part `Relaxed`.

Note: This method is only available on platforms that support atomic operations on `u8`.

# Examples

    use std::sync::atomic::{AtomicBool, Ordering};

    let foo = AtomicBool::new(true);
    assert_eq!(foo.fetch_nand(false, Ordering::SeqCst), true);
    assert_eq!(foo.load(Ordering::SeqCst), true);

    let foo = AtomicBool::new(true);
    assert_eq!(foo.fetch_nand(true, Ordering::SeqCst), true);
    assert_eq!(foo.load(Ordering::SeqCst) as usize, 0);
    assert_eq!(foo.load(Ordering::SeqCst), false);

    let foo = AtomicBool::new(false);
    assert_eq!(foo.fetch_nand(false, Ordering::SeqCst), false);
    assert_eq!(foo.load(Ordering::SeqCst), true);

Run

#### `pub fn fetch_or(&self, val: bool, order: Ordering) -> bool`[src]

Logical "or" with a boolean value.

Performs a logical "or" operation on the current value and the argument `val`, and sets the new value to the result.

Returns the previous value.

`fetch_or` takes an `Ordering` argument which describes the memory ordering of this operation. All ordering modes are possible. Note that using `Acquire` makes the store part of this operation `Relaxed`, and using `Release` makes the load part `Relaxed`.

Note: This method is only available on platforms that support atomic operations on `u8`.

# Examples

    use std::sync::atomic::{AtomicBool, Ordering};

    let foo = AtomicBool::new(true);
    assert_eq!(foo.fetch_or(false, Ordering::SeqCst), true);
    assert_eq!(foo.load(Ordering::SeqCst), true);

    let foo = AtomicBool::new(true);
    assert_eq!(foo.fetch_or(true, Ordering::SeqCst), true);
    assert_eq!(foo.load(Ordering::SeqCst), true);

    let foo = AtomicBool::new(false);
    assert_eq!(foo.fetch_or(false, Ordering::SeqCst), false);
    assert_eq!(foo.load(Ordering::SeqCst), false);

Run

#### `pub fn fetch_xor(&self, val: bool, order: Ordering) -> bool`[src]

Logical "xor" with a boolean value.

Performs a logical "xor" operation on the current value and the argument `val`, and sets the new value to the result.

Returns the previous value.

`fetch_xor` takes an `Ordering` argument which describes the memory ordering of this operation. All ordering modes are possible. Note that using `Acquire` makes the store part of this operation `Relaxed`, and using `Release` makes the load part `Relaxed`.

Note: This method is only available on platforms that support atomic operations on `u8`.

# Examples

    use std::sync::atomic::{AtomicBool, Ordering};

    let foo = AtomicBool::new(true);
    assert_eq!(foo.fetch_xor(false, Ordering::SeqCst), true);
    assert_eq!(foo.load(Ordering::SeqCst), true);

    let foo = AtomicBool::new(true);
    assert_eq!(foo.fetch_xor(true, Ordering::SeqCst), true);
    assert_eq!(foo.load(Ordering::SeqCst), false);

    let foo = AtomicBool::new(false);
    assert_eq!(foo.fetch_xor(false, Ordering::SeqCst), false);
    assert_eq!(foo.load(Ordering::SeqCst), false);

Run

#### `pub fn as_mut_ptr(&self) -> *mut bool`[src]

🔬 This is a nightly-only experimental API. (`atomic_mut_ptr` #66893)

recently added

Returns a mutable pointer to the underlying `bool`.

Doing non-atomic reads and writes on the resulting integer can be a data race. This method is mostly useful for FFI, where the function signature may use `*mut bool` instead of `&AtomicBool`.

Returning an `*mut` pointer from a shared reference to this atomic is safe because the atomic types work with interior mutability. All modifications of an atomic change the value through a shared reference, and can do so safely as long as they use atomic operations. Any use of the returned raw pointer requires an `unsafe` block and still has to uphold the same restriction: operations on it must be atomic.

# Examples

ⓘThis example is not tested

    use std::sync::atomic::AtomicBool;
    extern {
        fn my_atomic_op(arg: *mut bool);
    }

    let mut atomic = AtomicBool::new(true);
    unsafe {
        my_atomic_op(atomic.as_mut_ptr());
    }

Run

## Trait Implementations

### `impl Debug for AtomicBool` 1.3.0[src]

#### `fn fmt(&self, f: &mut Formatter<'_>) -> Result`[src]

Formats the value using the given formatter. Read more

### `impl Default for AtomicBool`[src]

#### `fn default() -> Self`[src]

Creates an `AtomicBool` initialized to `false`.

### `impl From<bool> for AtomicBool` 1.24.0[src]

#### `fn from(b: bool) -> Self`[src]

Converts a `bool` into an `AtomicBool`.

# Examples

    use std::sync::atomic::AtomicBool;
    let atomic_bool = AtomicBool::from(true);
    assert_eq!(format!("{:?}", atomic_bool), "true")

Run

### `impl Sync for AtomicBool`[src]

## Auto Trait Implementations

### `impl Send for AtomicBool`

### `impl Unpin for AtomicBool`

## Blanket Implementations

### `impl<T> Any for T where
T: 'static + ?Sized,` [src]

#### `fn type_id(&Self) -> TypeId`[src]

Gets the `TypeId` of `self`. Read more

### `impl<T> Borrow<T> for T where
T: ?Sized,` [src]

#### `fn borrow(&Self) -> &T`[src]

Immutably borrows from an owned value. Read more

### `impl<T> BorrowMut<T> for T where
T: ?Sized,` [src]

#### `fn borrow_mut(&mut Self) -> &mut T`[src]

Mutably borrows from an owned value. Read more

### `impl<T> From<T> for T`[src]

#### `fn from(T) -> T`[src]

Performs the conversion.

### `impl<T, U> Into<U> for T where
U: From<T>,` [src]

#### `fn into(Self) -> U`[src]

Performs the conversion.

### `impl<T, U> TryFrom<U> for T where
U: Into<T>,` [src]

#### `type Error = Infallible`

The type returned in the event of a conversion error.

#### `fn try_from(U) -> Result<T, <T as TryFrom<U>>::Error>`[src]

Performs the conversion.

### `impl<T, U> TryInto<U> for T where
U: TryFrom<T>,` [src]

#### `type Error = <U as TryFrom<T>>::Error`

The type returned in the event of a conversion error.

#### `fn try_into(Self) -> Result<U, <U as TryFrom<T>>::Error>`[src]

Performs the conversion.