Struct secmem_alloc::boxed::Box

pub struct Box<T: ?Sized, A: Allocator> { /* private fields */ }

A replacement for std::boxed::Box that works with custom allocators.

See the module-level documentation for more.

Implementations

impl<T, A: Allocator> Box<T, A>

pub fn new_in(x: T, alloc: A) -> Self

Allocates memory in the given allocator then places x into it.

This doesn’t actually allocate if T is zero-sized.

Examples

#![feature(allocator_api)]

use secmem_alloc::boxed::Box;
use std::alloc::System;

let five = Box::new_in(5, System);

pub fn try_new_in(x: T, alloc: A) -> Result<Self, AllocError>

Allocates memory in the given allocator then places x into it, returning an error if the allocation fails

This doesn’t actually allocate if T is zero-sized.

Examples

#![feature(allocator_api)]

use secmem_alloc::boxed::Box;
use std::alloc::System;

let five = Box::try_new_in(5, System)?;

pub fn new_uninit_in(alloc: A) -> Box<MaybeUninit<T>, A>

Constructs a new box with uninitialized contents in the provided allocator.

Examples

#![feature(allocator_api)]

use secmem_alloc::boxed::Box;
use std::alloc::System;

let mut five = Box::<u32, _>::new_uninit_in(System);

let five = unsafe {
    // Deferred initialization:
    five.as_mut_ptr().write(5);

    five.assume_init()
};

assert_eq!(*five, 5)

pub fn try_new_uninit_in(alloc: A) -> Result<Box<MaybeUninit<T>, A>, AllocError>

Constructs a new box with uninitialized contents in the provided allocator, returning an error if the allocation fails

Examples

#![feature(allocator_api)]

use secmem_alloc::boxed::Box;
use std::alloc::System;

let mut five = Box::<u32, _>::try_new_uninit_in(System)?;

let five = unsafe {
    // Deferred initialization:
    five.as_mut_ptr().write(5);

    five.assume_init()
};

assert_eq!(*five, 5);

impl<T, A: Allocator> Box<MaybeUninit<T>, A>

pub unsafe fn assume_init(self) -> Box<T, A>

Converts to Box<T, A>.

Safety

As with MaybeUninit::assume_init, it is up to the caller to guarantee that the value really is in an initialized state. Calling this when the content is not yet fully initialized causes immediate undefined behavior.

Examples

#![feature(allocator_api)]

use secmem_alloc::boxed::Box;
use std::alloc::System;

let mut five = Box::<u32, _>::new_uninit_in(System);

let five: Box<u32, _> = unsafe {
    // Deferred initialization:
    five.as_mut_ptr().write(5);

    five.assume_init()
};

assert_eq!(*five, 5)

Trait Implementations

impl<T: ?Sized, A: Allocator> Deref for Box<T, A>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &T

Dereferences the value.

impl<T: ?Sized, A: Allocator> DerefMut for Box<T, A>

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

Mutably dereferences the value.

impl<T: ?Sized, A: Allocator> Drop for Box<T, A>

fn drop(&mut self)

Executes the destructor for this type.