Struct alloc::boxed::PinBox

#[repr(transparent)]
pub struct PinBox<T: ?Sized> { /* fields omitted */ }

🔬 This is a nightly-only experimental API. (pin #49150)

A pinned, heap allocated reference.

Methods

impl<T> PinBox<T>

pub fn new(data: T) -> PinBox<T>

🔬 This is a nightly-only experimental API. (pin #49150)

Allocate memory on the heap, move the data into it and pin it.

impl<T: ?Sized> PinBox<T>

pub fn as_pin_mut<'a>(&'a mut self) -> PinMut<'a, T>

🔬 This is a nightly-only experimental API. (pin #49150)

Get a pinned reference to the data in this PinBox.

pub unsafe fn from_raw(raw: *mut T) -> Self

🔬 This is a nightly-only experimental API. (pin #49150)

Constructs a PinBox from a raw pointer.

After calling this function, the raw pointer is owned by the resulting PinBox. Specifically, the PinBox destructor will call the destructor of T and free the allocated memory. Since the way PinBox allocates and releases memory is unspecified, the only valid pointer to pass to this function is the one taken from another PinBox via the PinBox::into_raw function.

This function is unsafe because improper use may lead to memory problems. For example, a double-free may occur if the function is called twice on the same raw pointer.

Examples

#![feature(pin)]
use std::boxed::PinBox;
let x = PinBox::new(5);
let ptr = PinBox::into_raw(x);
let x = unsafe { PinBox::from_raw(ptr) };

pub fn into_raw(b: PinBox<T>) -> *mut T

🔬 This is a nightly-only experimental API. (pin #49150)

Consumes the PinBox, returning the wrapped raw pointer.

After calling this function, the caller is responsible for the memory previously managed by the PinBox. In particular, the caller should properly destroy T and release the memory. The proper way to do so is to convert the raw pointer back into a PinBox with the PinBox::from_raw function.

Note: this is an associated function, which means that you have to call it as PinBox::into_raw(b) instead of b.into_raw(). This is so that there is no conflict with a method on the inner type.

Examples

#![feature(pin)]
use std::boxed::PinBox;
let x = PinBox::new(5);
let ptr = PinBox::into_raw(x);

pub unsafe fn get_mut<'a>(this: &'a mut PinBox<T>) -> &'a mut T

🔬 This is a nightly-only experimental API. (pin #49150)

Get a mutable reference to the data inside this PinBox.

This function is unsafe. Users must guarantee that the data is never moved out of this reference.

Important traits for Box<I>

impl<I: Iterator + ?Sized> Iterator for Box<I> type Item = I::Item;

pub unsafe fn unpin(this: PinBox<T>) -> Box<T>

🔬 This is a nightly-only experimental API. (pin #49150)

Convert this PinBox into an unpinned Box.

This function is unsafe. Users must guarantee that the data is never moved out of the box.

Trait Implementations

impl<T: ?Sized> From<Box<T>> for PinBox<T>

fn from(boxed: Box<T>) -> PinBox<T>

Performs the conversion.

impl<T: Unpin + ?Sized> From<PinBox<T>> for Box<T>

Important traits for Box<I>

impl<I: Iterator + ?Sized> Iterator for Box<I> type Item = I::Item;

fn from(pinned: PinBox<T>) -> Box<T>

Performs the conversion.

impl<T: ?Sized> Deref for PinBox<T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &T

Dereferences the value.

impl<T: Unpin + ?Sized> DerefMut for PinBox<T>

fn deref_mut(&mut self) -> &mut T

Mutably dereferences the value.

impl<T: Display + ?Sized> Display for PinBox<T>

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<T: Debug + ?Sized> Debug for PinBox<T>

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<T: ?Sized> Pointer for PinBox<T>

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<PinBox<U>> for PinBox<T>

impl<T: ?Sized> Unpin for PinBox<T>

impl<'a, F: ?Sized + Future> Future for PinBox<F>

type Output = F::Output

🔬 This is a nightly-only experimental API. (futures_api #50547)

futures in libcore are unstable

The result of the Future.

fn poll(self: PinMut<Self>, cx: &mut Context) -> Poll<Self::Output>

🔬 This is a nightly-only experimental API. (futures_api #50547)

futures in libcore are unstable

Attempt to resolve the future to a final value, registering the current task for wakeup if the value is not yet available.

impl<F: Future<Output = ()> + Send + 'static> UnsafeTask for PinBox<F>

fn into_raw(self) -> *mut ()

🔬 This is a nightly-only experimental API. (futures_api #50547)

futures in libcore are unstable

Convert a owned instance into a (conceptually owned) void pointer.

unsafe fn poll(task: *mut (), cx: &mut Context) -> Poll<()>

🔬 This is a nightly-only experimental API. (futures_api #50547)

futures in libcore are unstable

Poll the task represented by the given void pointer.

unsafe fn drop(task: *mut ())

🔬 This is a nightly-only experimental API. (futures_api #50547)

futures in libcore are unstable

Drops the task represented by the given void pointer.

impl<F: Future<Output = ()> + Send + 'static> From<PinBox<F>> for TaskObj

fn from(boxed: PinBox<F>) -> Self

Performs the conversion.