pub type DebugCallback = Box<dyn Fn(u32, u32, u32, u32, &str) + Send + Sync>;
Aliased Typeยง
struct DebugCallback(/* private fields */);
Implementations
Sourceยงimpl<T> Box<T>where
T: ?Sized,
impl<T> Box<T>where
T: ?Sized,
1.4.0 ยท Sourcepub unsafe fn from_raw(raw: *mut T) -> Box<T>
pub unsafe fn from_raw(raw: *mut T) -> Box<T>
Constructs a box from a raw pointer.
After calling this function, the raw pointer is owned by the
resulting Box
. Specifically, the Box
destructor will call
the destructor of T
and free the allocated memory. For this
to be safe, the memory must have been allocated in accordance
with the memory layout used by Box
.
ยงSafety
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.
The safety conditions are described in the memory layout section.
ยงExamples
Recreate a Box
which was previously converted to a raw pointer
using Box::into_raw
:
let x = Box::new(5);
let ptr = Box::into_raw(x);
let x = unsafe { Box::from_raw(ptr) };
Manually create a Box
from scratch by using the global allocator:
use std::alloc::{alloc, Layout};
unsafe {
let ptr = alloc(Layout::new::<i32>()) as *mut i32;
// In general .write is required to avoid attempting to destruct
// the (uninitialized) previous contents of `ptr`, though for this
// simple example `*ptr = 5` would have worked as well.
ptr.write(5);
let x = Box::from_raw(ptr);
}
Sourcepub unsafe fn from_non_null(ptr: NonNull<T>) -> Box<T>
๐ฌThis is a nightly-only experimental API. (box_vec_non_null
)
pub unsafe fn from_non_null(ptr: NonNull<T>) -> Box<T>
box_vec_non_null
)Constructs a box from a NonNull
pointer.
After calling this function, the NonNull
pointer is owned by
the resulting Box
. Specifically, the Box
destructor will call
the destructor of T
and free the allocated memory. For this
to be safe, the memory must have been allocated in accordance
with the memory layout used by Box
.
ยงSafety
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 NonNull
pointer.
The safety conditions are described in the memory layout section.
ยงExamples
Recreate a Box
which was previously converted to a NonNull
pointer using Box::into_non_null
:
#![feature(box_vec_non_null)]
let x = Box::new(5);
let non_null = Box::into_non_null(x);
let x = unsafe { Box::from_non_null(non_null) };
Manually create a Box
from scratch by using the global allocator:
#![feature(box_vec_non_null)]
use std::alloc::{alloc, Layout};
use std::ptr::NonNull;
unsafe {
let non_null = NonNull::new(alloc(Layout::new::<i32>()).cast::<i32>())
.expect("allocation failed");
// In general .write is required to avoid attempting to destruct
// the (uninitialized) previous contents of `non_null`.
non_null.write(5);
let x = Box::from_non_null(non_null);
}
Sourceยงimpl<T> Box<T>
impl<T> Box<T>
1.0.0 ยท Sourcepub fn new(x: T) -> Box<T>
pub fn new(x: T) -> Box<T>
Allocates memory on the heap and then places x
into it.
This doesnโt actually allocate if T
is zero-sized.
ยงExamples
let five = Box::new(5);
1.82.0 ยท Sourcepub fn new_uninit() -> Box<MaybeUninit<T>>
pub fn new_uninit() -> Box<MaybeUninit<T>>
Constructs a new box with uninitialized contents.
ยงExamples
let mut five = Box::<u32>::new_uninit();
let five = unsafe {
// Deferred initialization:
five.as_mut_ptr().write(5);
five.assume_init()
};
assert_eq!(*five, 5)
Sourcepub fn new_zeroed() -> Box<MaybeUninit<T>>
๐ฌThis is a nightly-only experimental API. (new_zeroed_alloc
)
pub fn new_zeroed() -> Box<MaybeUninit<T>>
new_zeroed_alloc
)Constructs a new Box
with uninitialized contents, with the memory
being filled with 0
bytes.
See MaybeUninit::zeroed
for examples of correct and incorrect usage
of this method.
ยงExamples
#![feature(new_zeroed_alloc)]
let zero = Box::<u32>::new_zeroed();
let zero = unsafe { zero.assume_init() };
assert_eq!(*zero, 0)
1.33.0 ยท Sourcepub fn pin(x: T) -> Pin<Box<T>>
pub fn pin(x: T) -> Pin<Box<T>>
Constructs a new Pin<Box<T>>
. If T
does not implement Unpin
, then
x
will be pinned in memory and unable to be moved.
Constructing and pinning of the Box
can also be done in two steps: Box::pin(x)
does the same as Box::into_pin(Box::new(x))
. Consider using
into_pin
if you already have a Box<T>
, or if you want to
construct a (pinned) Box
in a different way than with Box::new
.
Sourcepub fn try_new(x: T) -> Result<Box<T>, AllocError>
๐ฌThis is a nightly-only experimental API. (allocator_api
)
pub fn try_new(x: T) -> Result<Box<T>, AllocError>
allocator_api
)Allocates memory on the heap then places x
into it,
returning an error if the allocation fails
This doesnโt actually allocate if T
is zero-sized.
ยงExamples
#![feature(allocator_api)]
let five = Box::try_new(5)?;
Sourcepub fn try_new_uninit() -> Result<Box<MaybeUninit<T>>, AllocError>
๐ฌThis is a nightly-only experimental API. (allocator_api
)
pub fn try_new_uninit() -> Result<Box<MaybeUninit<T>>, AllocError>
allocator_api
)Constructs a new box with uninitialized contents on the heap, returning an error if the allocation fails
ยงExamples
#![feature(allocator_api)]
let mut five = Box::<u32>::try_new_uninit()?;
let five = unsafe {
// Deferred initialization:
five.as_mut_ptr().write(5);
five.assume_init()
};
assert_eq!(*five, 5);
Sourcepub fn try_new_zeroed() -> Result<Box<MaybeUninit<T>>, AllocError>
๐ฌThis is a nightly-only experimental API. (allocator_api
)
pub fn try_new_zeroed() -> Result<Box<MaybeUninit<T>>, AllocError>
allocator_api
)Constructs a new Box
with uninitialized contents, with the memory
being filled with 0
bytes on the heap
See MaybeUninit::zeroed
for examples of correct and incorrect usage
of this method.
ยงExamples
#![feature(allocator_api)]
let zero = Box::<u32>::try_new_zeroed()?;
let zero = unsafe { zero.assume_init() };
assert_eq!(*zero, 0);
Sourceยงimpl<T, A> Box<T, A>
impl<T, A> Box<T, A>
Sourcepub const unsafe fn from_raw_in(raw: *mut T, alloc: A) -> Box<T, A>
๐ฌThis is a nightly-only experimental API. (allocator_api
)
pub const unsafe fn from_raw_in(raw: *mut T, alloc: A) -> Box<T, A>
allocator_api
)Constructs a box from a raw pointer in the given allocator.
After calling this function, the raw pointer is owned by the
resulting Box
. Specifically, the Box
destructor will call
the destructor of T
and free the allocated memory. For this
to be safe, the memory must have been allocated in accordance
with the memory layout used by Box
.
ยงSafety
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.
ยงExamples
Recreate a Box
which was previously converted to a raw pointer
using Box::into_raw_with_allocator
:
#![feature(allocator_api)]
use std::alloc::System;
let x = Box::new_in(5, System);
let (ptr, alloc) = Box::into_raw_with_allocator(x);
let x = unsafe { Box::from_raw_in(ptr, alloc) };
Manually create a Box
from scratch by using the system allocator:
#![feature(allocator_api, slice_ptr_get)]
use std::alloc::{Allocator, Layout, System};
unsafe {
let ptr = System.allocate(Layout::new::<i32>())?.as_mut_ptr() as *mut i32;
// In general .write is required to avoid attempting to destruct
// the (uninitialized) previous contents of `ptr`, though for this
// simple example `*ptr = 5` would have worked as well.
ptr.write(5);
let x = Box::from_raw_in(ptr, System);
}
Sourcepub const unsafe fn from_non_null_in(raw: NonNull<T>, alloc: A) -> Box<T, A>
๐ฌThis is a nightly-only experimental API. (allocator_api
)
pub const unsafe fn from_non_null_in(raw: NonNull<T>, alloc: A) -> Box<T, A>
allocator_api
)Constructs a box from a NonNull
pointer in the given allocator.
After calling this function, the NonNull
pointer is owned by
the resulting Box
. Specifically, the Box
destructor will call
the destructor of T
and free the allocated memory. For this
to be safe, the memory must have been allocated in accordance
with the memory layout used by Box
.
ยงSafety
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.
ยงExamples
Recreate a Box
which was previously converted to a NonNull
pointer
using Box::into_non_null_with_allocator
:
#![feature(allocator_api, box_vec_non_null)]
use std::alloc::System;
let x = Box::new_in(5, System);
let (non_null, alloc) = Box::into_non_null_with_allocator(x);
let x = unsafe { Box::from_non_null_in(non_null, alloc) };
Manually create a Box
from scratch by using the system allocator:
#![feature(allocator_api, box_vec_non_null, slice_ptr_get)]
use std::alloc::{Allocator, Layout, System};
unsafe {
let non_null = System.allocate(Layout::new::<i32>())?.cast::<i32>();
// In general .write is required to avoid attempting to destruct
// the (uninitialized) previous contents of `non_null`.
non_null.write(5);
let x = Box::from_non_null_in(non_null, System);
}
1.4.0 ยท Sourcepub fn into_raw(b: Box<T, A>) -> *mut T
pub fn into_raw(b: Box<T, A>) -> *mut T
Consumes the Box
, returning a wrapped raw pointer.
The pointer will be properly aligned and non-null.
After calling this function, the caller is responsible for the
memory previously managed by the Box
. In particular, the
caller should properly destroy T
and release the memory, taking
into account the memory layout used by Box
. The easiest way to
do this is to convert the raw pointer back into a Box
with the
Box::from_raw
function, allowing the Box
destructor to perform
the cleanup.
Note: this is an associated function, which means that you have
to call it as Box::into_raw(b)
instead of b.into_raw()
. This
is so that there is no conflict with a method on the inner type.
ยงExamples
Converting the raw pointer back into a Box
with Box::from_raw
for automatic cleanup:
let x = Box::new(String::from("Hello"));
let ptr = Box::into_raw(x);
let x = unsafe { Box::from_raw(ptr) };
Manual cleanup by explicitly running the destructor and deallocating the memory:
use std::alloc::{dealloc, Layout};
use std::ptr;
let x = Box::new(String::from("Hello"));
let ptr = Box::into_raw(x);
unsafe {
ptr::drop_in_place(ptr);
dealloc(ptr as *mut u8, Layout::new::<String>());
}
Note: This is equivalent to the following:
let x = Box::new(String::from("Hello"));
let ptr = Box::into_raw(x);
unsafe {
drop(Box::from_raw(ptr));
}
Sourcepub fn into_non_null(b: Box<T, A>) -> NonNull<T>
๐ฌThis is a nightly-only experimental API. (box_vec_non_null
)
pub fn into_non_null(b: Box<T, A>) -> NonNull<T>
box_vec_non_null
)Consumes the Box
, returning a wrapped NonNull
pointer.
The pointer will be properly aligned.
After calling this function, the caller is responsible for the
memory previously managed by the Box
. In particular, the
caller should properly destroy T
and release the memory, taking
into account the memory layout used by Box
. The easiest way to
do this is to convert the NonNull
pointer back into a Box
with the
Box::from_non_null
function, allowing the Box
destructor to
perform the cleanup.
Note: this is an associated function, which means that you have
to call it as Box::into_non_null(b)
instead of b.into_non_null()
.
This is so that there is no conflict with a method on the inner type.
ยงExamples
Converting the NonNull
pointer back into a Box
with Box::from_non_null
for automatic cleanup:
#![feature(box_vec_non_null)]
let x = Box::new(String::from("Hello"));
let non_null = Box::into_non_null(x);
let x = unsafe { Box::from_non_null(non_null) };
Manual cleanup by explicitly running the destructor and deallocating the memory:
#![feature(box_vec_non_null)]
use std::alloc::{dealloc, Layout};
let x = Box::new(String::from("Hello"));
let non_null = Box::into_non_null(x);
unsafe {
non_null.drop_in_place();
dealloc(non_null.as_ptr().cast::<u8>(), Layout::new::<String>());
}
Note: This is equivalent to the following:
#![feature(box_vec_non_null)]
let x = Box::new(String::from("Hello"));
let non_null = Box::into_non_null(x);
unsafe {
drop(Box::from_non_null(non_null));
}
Sourcepub fn into_raw_with_allocator(b: Box<T, A>) -> (*mut T, A)
๐ฌThis is a nightly-only experimental API. (allocator_api
)
pub fn into_raw_with_allocator(b: Box<T, A>) -> (*mut T, A)
allocator_api
)Consumes the Box
, returning a wrapped raw pointer and the allocator.
The pointer will be properly aligned and non-null.
After calling this function, the caller is responsible for the
memory previously managed by the Box
. In particular, the
caller should properly destroy T
and release the memory, taking
into account the memory layout used by Box
. The easiest way to
do this is to convert the raw pointer back into a Box
with the
Box::from_raw_in
function, allowing the Box
destructor to perform
the cleanup.
Note: this is an associated function, which means that you have
to call it as Box::into_raw_with_allocator(b)
instead of b.into_raw_with_allocator()
. This
is so that there is no conflict with a method on the inner type.
ยงExamples
Converting the raw pointer back into a Box
with Box::from_raw_in
for automatic cleanup:
#![feature(allocator_api)]
use std::alloc::System;
let x = Box::new_in(String::from("Hello"), System);
let (ptr, alloc) = Box::into_raw_with_allocator(x);
let x = unsafe { Box::from_raw_in(ptr, alloc) };
Manual cleanup by explicitly running the destructor and deallocating the memory:
#![feature(allocator_api)]
use std::alloc::{Allocator, Layout, System};
use std::ptr::{self, NonNull};
let x = Box::new_in(String::from("Hello"), System);
let (ptr, alloc) = Box::into_raw_with_allocator(x);
unsafe {
ptr::drop_in_place(ptr);
let non_null = NonNull::new_unchecked(ptr);
alloc.deallocate(non_null.cast(), Layout::new::<String>());
}
Sourcepub fn into_non_null_with_allocator(b: Box<T, A>) -> (NonNull<T>, A)
๐ฌThis is a nightly-only experimental API. (allocator_api
)
pub fn into_non_null_with_allocator(b: Box<T, A>) -> (NonNull<T>, A)
allocator_api
)Consumes the Box
, returning a wrapped NonNull
pointer and the allocator.
The pointer will be properly aligned.
After calling this function, the caller is responsible for the
memory previously managed by the Box
. In particular, the
caller should properly destroy T
and release the memory, taking
into account the memory layout used by Box
. The easiest way to
do this is to convert the NonNull
pointer back into a Box
with the
Box::from_non_null_in
function, allowing the Box
destructor to
perform the cleanup.
Note: this is an associated function, which means that you have
to call it as Box::into_non_null_with_allocator(b)
instead of
b.into_non_null_with_allocator()
. This is so that there is no
conflict with a method on the inner type.
ยงExamples
Converting the NonNull
pointer back into a Box
with
Box::from_non_null_in
for automatic cleanup:
#![feature(allocator_api, box_vec_non_null)]
use std::alloc::System;
let x = Box::new_in(String::from("Hello"), System);
let (non_null, alloc) = Box::into_non_null_with_allocator(x);
let x = unsafe { Box::from_non_null_in(non_null, alloc) };
Manual cleanup by explicitly running the destructor and deallocating the memory:
#![feature(allocator_api, box_vec_non_null)]
use std::alloc::{Allocator, Layout, System};
let x = Box::new_in(String::from("Hello"), System);
let (non_null, alloc) = Box::into_non_null_with_allocator(x);
unsafe {
non_null.drop_in_place();
alloc.deallocate(non_null.cast::<u8>(), Layout::new::<String>());
}
Sourcepub fn as_mut_ptr(b: &mut Box<T, A>) -> *mut T
๐ฌThis is a nightly-only experimental API. (box_as_ptr
)
pub fn as_mut_ptr(b: &mut Box<T, A>) -> *mut T
box_as_ptr
)Returns a raw mutable pointer to the Box
โs contents.
The caller must ensure that the Box
outlives the pointer this
function returns, or else it will end up dangling.
This method guarantees that for the purpose of the aliasing model, this method
does not materialize a reference to the underlying memory, and thus the returned pointer
will remain valid when mixed with other calls to as_ptr
and as_mut_ptr
.
Note that calling other methods that materialize references to the memory
may still invalidate this pointer.
See the example below for how this guarantee can be used.
ยงExamples
Due to the aliasing guarantee, the following code is legal:
#![feature(box_as_ptr)]
unsafe {
let mut b = Box::new(0);
let ptr1 = Box::as_mut_ptr(&mut b);
ptr1.write(1);
let ptr2 = Box::as_mut_ptr(&mut b);
ptr2.write(2);
// Notably, the write to `ptr2` did *not* invalidate `ptr1`:
ptr1.write(3);
}
Sourcepub fn as_ptr(b: &Box<T, A>) -> *const T
๐ฌThis is a nightly-only experimental API. (box_as_ptr
)
pub fn as_ptr(b: &Box<T, A>) -> *const T
box_as_ptr
)Returns a raw pointer to the Box
โs contents.
The caller must ensure that the Box
outlives the pointer this
function returns, or else it will end up dangling.
The caller must also ensure that the memory the pointer (non-transitively) points to
is never written to (except inside an UnsafeCell
) using this pointer or any pointer
derived from it. If you need to mutate the contents of the Box
, use as_mut_ptr
.
This method guarantees that for the purpose of the aliasing model, this method
does not materialize a reference to the underlying memory, and thus the returned pointer
will remain valid when mixed with other calls to as_ptr
and as_mut_ptr
.
Note that calling other methods that materialize mutable references to the memory,
as well as writing to this memory, may still invalidate this pointer.
See the example below for how this guarantee can be used.
ยงExamples
Due to the aliasing guarantee, the following code is legal:
#![feature(box_as_ptr)]
unsafe {
let mut v = Box::new(0);
let ptr1 = Box::as_ptr(&v);
let ptr2 = Box::as_mut_ptr(&mut v);
let _val = ptr2.read();
// No write to this memory has happened yet, so `ptr1` is still valid.
let _val = ptr1.read();
// However, once we do a write...
ptr2.write(1);
// ... `ptr1` is no longer valid.
// This would be UB: let _val = ptr1.read();
}
Sourcepub const fn allocator(b: &Box<T, A>) -> &A
๐ฌThis is a nightly-only experimental API. (allocator_api
)
pub const fn allocator(b: &Box<T, A>) -> &A
allocator_api
)Returns a reference to the underlying allocator.
Note: this is an associated function, which means that you have
to call it as Box::allocator(&b)
instead of b.allocator()
. This
is so that there is no conflict with a method on the inner type.
1.26.0 ยท Sourcepub fn leak<'a>(b: Box<T, A>) -> &'a mut Twhere
A: 'a,
pub fn leak<'a>(b: Box<T, A>) -> &'a mut Twhere
A: 'a,
Consumes and leaks the Box
, returning a mutable reference,
&'a mut T
.
Note that the type T
must outlive the chosen lifetime 'a
. If the type
has only static references, or none at all, then this may be chosen to be
'static
.
This function is mainly useful for data that lives for the remainder of
the programโs life. Dropping the returned reference will cause a memory
leak. If this is not acceptable, the reference should first be wrapped
with the Box::from_raw
function producing a Box
. This Box
can
then be dropped which will properly destroy T
and release the
allocated memory.
Note: this is an associated function, which means that you have
to call it as Box::leak(b)
instead of b.leak()
. This
is so that there is no conflict with a method on the inner type.
ยงExamples
Simple usage:
let x = Box::new(41);
let static_ref: &'static mut usize = Box::leak(x);
*static_ref += 1;
assert_eq!(*static_ref, 42);
Unsized data:
let x = vec![1, 2, 3].into_boxed_slice();
let static_ref = Box::leak(x);
static_ref[0] = 4;
assert_eq!(*static_ref, [4, 2, 3]);
1.63.0 (const: unstable) ยท Sourcepub fn into_pin(boxed: Box<T, A>) -> Pin<Box<T, A>>where
A: 'static,
pub fn into_pin(boxed: Box<T, A>) -> Pin<Box<T, A>>where
A: 'static,
Converts a Box<T>
into a Pin<Box<T>>
. If T
does not implement Unpin
, then
*boxed
will be pinned in memory and unable to be moved.
This conversion does not allocate on the heap and happens in place.
This is also available via From
.
Constructing and pinning a Box
with Box::into_pin(Box::new(x))
can also be written more concisely using Box::pin(x)
.
This into_pin
method is useful if you already have a Box<T>
, or you are
constructing a (pinned) Box
in a different way than with Box::new
.
ยงNotes
Itโs not recommended that crates add an impl like From<Box<T>> for Pin<T>
,
as itโll introduce an ambiguity when calling Pin::from
.
A demonstration of such a poor impl is shown below.
struct Foo; // A type defined in this crate.
impl From<Box<()>> for Pin<Foo> {
fn from(_: Box<()>) -> Pin<Foo> {
Pin::new(Foo)
}
}
let foo = Box::new(());
let bar = Pin::from(foo);
Sourceยงimpl<T, A> Box<T, A>where
A: Allocator,
impl<T, A> Box<T, A>where
A: Allocator,
Sourcepub fn new_in(x: T, alloc: A) -> Box<T, A>where
A: Allocator,
๐ฌThis is a nightly-only experimental API. (allocator_api
)
pub fn new_in(x: T, alloc: A) -> Box<T, A>where
A: Allocator,
allocator_api
)Allocates memory in the given allocator then places x
into it.
This doesnโt actually allocate if T
is zero-sized.
ยงExamples
#![feature(allocator_api)]
use std::alloc::System;
let five = Box::new_in(5, System);
Sourcepub fn try_new_in(x: T, alloc: A) -> Result<Box<T, A>, AllocError>where
A: Allocator,
๐ฌThis is a nightly-only experimental API. (allocator_api
)
pub fn try_new_in(x: T, alloc: A) -> Result<Box<T, A>, AllocError>where
A: Allocator,
allocator_api
)Allocates memory in the given allocator then places x
into it,
returning an error if the allocation fails
This doesnโt actually allocate if T
is zero-sized.
ยงExamples
#![feature(allocator_api)]
use std::alloc::System;
let five = Box::try_new_in(5, System)?;
Sourcepub fn new_uninit_in(alloc: A) -> Box<MaybeUninit<T>, A>where
A: Allocator,
๐ฌThis is a nightly-only experimental API. (allocator_api
)
pub fn new_uninit_in(alloc: A) -> Box<MaybeUninit<T>, A>where
A: Allocator,
allocator_api
)Constructs a new box with uninitialized contents in the provided allocator.
ยงExamples
#![feature(allocator_api)]
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)
Sourcepub fn try_new_uninit_in(alloc: A) -> Result<Box<MaybeUninit<T>, A>, AllocError>where
A: Allocator,
๐ฌThis is a nightly-only experimental API. (allocator_api
)
pub fn try_new_uninit_in(alloc: A) -> Result<Box<MaybeUninit<T>, A>, AllocError>where
A: Allocator,
allocator_api
)Constructs a new box with uninitialized contents in the provided allocator, returning an error if the allocation fails
ยงExamples
#![feature(allocator_api)]
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);
Sourcepub fn new_zeroed_in(alloc: A) -> Box<MaybeUninit<T>, A>where
A: Allocator,
๐ฌThis is a nightly-only experimental API. (allocator_api
)
pub fn new_zeroed_in(alloc: A) -> Box<MaybeUninit<T>, A>where
A: Allocator,
allocator_api
)Constructs a new Box
with uninitialized contents, with the memory
being filled with 0
bytes in the provided allocator.
See MaybeUninit::zeroed
for examples of correct and incorrect usage
of this method.
ยงExamples
#![feature(allocator_api)]
use std::alloc::System;
let zero = Box::<u32, _>::new_zeroed_in(System);
let zero = unsafe { zero.assume_init() };
assert_eq!(*zero, 0)
Sourcepub fn try_new_zeroed_in(alloc: A) -> Result<Box<MaybeUninit<T>, A>, AllocError>where
A: Allocator,
๐ฌThis is a nightly-only experimental API. (allocator_api
)
pub fn try_new_zeroed_in(alloc: A) -> Result<Box<MaybeUninit<T>, A>, AllocError>where
A: Allocator,
allocator_api
)Constructs a new Box
with uninitialized contents, with the memory
being filled with 0
bytes in the provided allocator,
returning an error if the allocation fails,
See MaybeUninit::zeroed
for examples of correct and incorrect usage
of this method.
ยงExamples
#![feature(allocator_api)]
use std::alloc::System;
let zero = Box::<u32, _>::try_new_zeroed_in(System)?;
let zero = unsafe { zero.assume_init() };
assert_eq!(*zero, 0);
Sourcepub fn pin_in(x: T, alloc: A) -> Pin<Box<T, A>>where
A: 'static + Allocator,
๐ฌThis is a nightly-only experimental API. (allocator_api
)
pub fn pin_in(x: T, alloc: A) -> Pin<Box<T, A>>where
A: 'static + Allocator,
allocator_api
)Constructs a new Pin<Box<T, A>>
. If T
does not implement Unpin
, then
x
will be pinned in memory and unable to be moved.
Constructing and pinning of the Box
can also be done in two steps: Box::pin_in(x, alloc)
does the same as Box::into_pin(Box::new_in(x, alloc))
. Consider using
into_pin
if you already have a Box<T, A>
, or if you want to
construct a (pinned) Box
in a different way than with Box::new_in
.
Sourcepub fn into_boxed_slice(boxed: Box<T, A>) -> Box<[T], A>
๐ฌThis is a nightly-only experimental API. (box_into_boxed_slice
)
pub fn into_boxed_slice(boxed: Box<T, A>) -> Box<[T], A>
box_into_boxed_slice
)Converts a Box<T>
into a Box<[T]>
This conversion does not allocate on the heap and happens in place.
Sourcepub fn into_inner(boxed: Box<T, A>) -> T
๐ฌThis is a nightly-only experimental API. (box_into_inner
)
pub fn into_inner(boxed: Box<T, A>) -> T
box_into_inner
)Consumes the Box
, returning the wrapped value.
ยงExamples
#![feature(box_into_inner)]
let c = Box::new(5);
assert_eq!(Box::into_inner(c), 5);
Trait Implementations
1.64.0 ยท Sourceยงimpl<T> AsFd for Box<T>
impl<T> AsFd for Box<T>
Sourceยงfn as_fd(&self) -> BorrowedFd<'_>
fn as_fd(&self) -> BorrowedFd<'_>
Sourceยงimpl<Args, F, A> AsyncFn<Args> for Box<F, A>
impl<Args, F, A> AsyncFn<Args> for Box<F, A>
Sourceยงextern "rust-call" fn async_call(
&self,
args: Args,
) -> <Box<F, A> as AsyncFnMut<Args>>::CallRefFuture<'_>
extern "rust-call" fn async_call( &self, args: Args, ) -> <Box<F, A> as AsyncFnMut<Args>>::CallRefFuture<'_>
async_fn_traits
)AsyncFn
, returning a future which may borrow from the called closure.Sourceยงimpl<Args, F, A> AsyncFnMut<Args> for Box<F, A>
impl<Args, F, A> AsyncFnMut<Args> for Box<F, A>
Sourceยงtype CallRefFuture<'a> = <F as AsyncFnMut<Args>>::CallRefFuture<'a>
where
Box<F, A>: 'a
type CallRefFuture<'a> = <F as AsyncFnMut<Args>>::CallRefFuture<'a> where Box<F, A>: 'a
async_fn_traits
)AsyncFnMut::async_call_mut
and AsyncFn::async_call
.Sourceยงextern "rust-call" fn async_call_mut(
&mut self,
args: Args,
) -> <Box<F, A> as AsyncFnMut<Args>>::CallRefFuture<'_>
extern "rust-call" fn async_call_mut( &mut self, args: Args, ) -> <Box<F, A> as AsyncFnMut<Args>>::CallRefFuture<'_>
async_fn_traits
)AsyncFnMut
, returning a future which may borrow from the called closure.Sourceยงimpl<Args, F, A> AsyncFnOnce<Args> for Box<F, A>
impl<Args, F, A> AsyncFnOnce<Args> for Box<F, A>
Sourceยงtype Output = <F as AsyncFnOnce<Args>>::Output
type Output = <F as AsyncFnOnce<Args>>::Output
async_fn_traits
)Sourceยงtype CallOnceFuture = <F as AsyncFnOnce<Args>>::CallOnceFuture
type CallOnceFuture = <F as AsyncFnOnce<Args>>::CallOnceFuture
async_fn_traits
)AsyncFnOnce::async_call_once
.Sourceยงextern "rust-call" fn async_call_once(
self,
args: Args,
) -> <Box<F, A> as AsyncFnOnce<Args>>::CallOnceFuture
extern "rust-call" fn async_call_once( self, args: Args, ) -> <Box<F, A> as AsyncFnOnce<Args>>::CallOnceFuture
async_fn_traits
)AsyncFnOnce
, returning a future which may move out of the called closure.Sourceยงimpl<S> AsyncIterator for Box<S>
impl<S> AsyncIterator for Box<S>
Sourceยงtype Item = <S as AsyncIterator>::Item
type Item = <S as AsyncIterator>::Item
async_iterator
)Sourceยงfn poll_next(
self: Pin<&mut Box<S>>,
cx: &mut Context<'_>,
) -> Poll<Option<<Box<S> as AsyncIterator>::Item>>
fn poll_next( self: Pin<&mut Box<S>>, cx: &mut Context<'_>, ) -> Poll<Option<<Box<S> as AsyncIterator>::Item>>
async_iterator
)None
if the async iterator is exhausted. Read more1.1.0 ยท Sourceยงimpl<T, A> BorrowMut<T> for Box<T, A>
impl<T, A> BorrowMut<T> for Box<T, A>
Sourceยงfn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
1.0.0 ยท Sourceยงimpl<B> BufRead for Box<B>
impl<B> BufRead for Box<B>
Sourceยงfn fill_buf(&mut self) -> Result<&[u8], Error>
fn fill_buf(&mut self) -> Result<&[u8], Error>
Sourceยงfn consume(&mut self, amt: usize)
fn consume(&mut self, amt: usize)
amt
bytes have been consumed from the buffer,
so they should no longer be returned in calls to read
. Read moreSourceยงfn read_line(&mut self, buf: &mut String) -> Result<usize, Error>
fn read_line(&mut self, buf: &mut String) -> Result<usize, Error>
0xA
byte) is reached, and append
them to the provided String
buffer. Read moreSourceยงfn has_data_left(&mut self) -> Result<bool, Error>
fn has_data_left(&mut self) -> Result<bool, Error>
buf_read_has_data_left
)Read
has any data left to be read. Read more1.83.0 ยท Sourceยงfn skip_until(&mut self, byte: u8) -> Result<usize, Error>
fn skip_until(&mut self, byte: u8) -> Result<usize, Error>
byte
or EOF is reached. Read more1.0.0 ยท Sourceยงimpl<T, A> Clone for Box<T, A>
impl<T, A> Clone for Box<T, A>
Sourceยงfn clone(&self) -> Box<T, A>
fn clone(&self) -> Box<T, A>
Returns a new box with a clone()
of this boxโs contents.
ยงExamples
let x = Box::new(5);
let y = x.clone();
// The value is the same
assert_eq!(x, y);
// But they are unique objects
assert_ne!(&*x as *const i32, &*y as *const i32);
Sourceยงfn clone_from(&mut self, source: &Box<T, A>)
fn clone_from(&mut self, source: &Box<T, A>)
Copies source
โs contents into self
without creating a new allocation.
ยงExamples
let x = Box::new(5);
let mut y = Box::new(10);
let yp: *const i32 = &*y;
y.clone_from(&x);
// The value is the same
assert_eq!(x, y);
// And no allocation occurred
assert_eq!(yp, &*y);
Sourceยงimpl<G, R, A> Coroutine<R> for Box<G, A>
impl<G, R, A> Coroutine<R> for Box<G, A>
Sourceยงtype Yield = <G as Coroutine<R>>::Yield
type Yield = <G as Coroutine<R>>::Yield
coroutine_trait
)1.0.0 ยท Sourceยงimpl<I, A> DoubleEndedIterator for Box<I, A>
impl<I, A> DoubleEndedIterator for Box<I, A>
Sourceยงfn next_back(&mut self) -> Option<<I as Iterator>::Item>
fn next_back(&mut self) -> Option<<I as Iterator>::Item>
Sourceยงfn nth_back(&mut self, n: usize) -> Option<<I as Iterator>::Item>
fn nth_back(&mut self, n: usize) -> Option<<I as Iterator>::Item>
n
th element from the end of the iterator. Read moreSourceยงfn advance_back_by(&mut self, n: usize) -> Result<(), NonZero<usize>>
fn advance_back_by(&mut self, n: usize) -> Result<(), NonZero<usize>>
iter_advance_by
)n
elements. Read more1.27.0 ยท Sourceยงfn try_rfold<B, F, R>(&mut self, init: B, f: F) -> R
fn try_rfold<B, F, R>(&mut self, init: B, f: F) -> R
Iterator::try_fold()
: it takes
elements starting from the back of the iterator. Read more1.8.0 ยท Sourceยงimpl<E> Error for Box<E>where
E: Error,
impl<E> Error for Box<E>where
E: Error,
Sourceยงfn description(&self) -> &str
fn description(&self) -> &str
Sourceยงfn cause(&self) -> Option<&dyn Error>
fn cause(&self) -> Option<&dyn Error>
1.0.0 ยท Sourceยงimpl<I, A> ExactSizeIterator for Box<I, A>
impl<I, A> ExactSizeIterator for Box<I, A>
1.22.0 ยท Sourceยงimpl<T, A> Hasher for Box<T, A>
impl<T, A> Hasher for Box<T, A>
Sourceยงfn write_u128(&mut self, i: u128)
fn write_u128(&mut self, i: u128)
u128
into this hasher.Sourceยงfn write_usize(&mut self, i: usize)
fn write_usize(&mut self, i: usize)
usize
into this hasher.Sourceยงfn write_i128(&mut self, i: i128)
fn write_i128(&mut self, i: i128)
i128
into this hasher.Sourceยงfn write_isize(&mut self, i: isize)
fn write_isize(&mut self, i: isize)
isize
into this hasher.Sourceยงfn write_length_prefix(&mut self, len: usize)
fn write_length_prefix(&mut self, len: usize)
hasher_prefixfree_extras
)1.0.0 ยท Sourceยงimpl<I, A> Iterator for Box<I, A>
impl<I, A> Iterator for Box<I, A>
Sourceยงfn next(&mut self) -> Option<<I as Iterator>::Item>
fn next(&mut self) -> Option<<I as Iterator>::Item>
Sourceยงfn size_hint(&self) -> (usize, Option<usize>)
fn size_hint(&self) -> (usize, Option<usize>)
Sourceยงfn nth(&mut self, n: usize) -> Option<<I as Iterator>::Item>
fn nth(&mut self, n: usize) -> Option<<I as Iterator>::Item>
n
th element of the iterator. Read moreSourceยงfn last(self) -> Option<<I as Iterator>::Item>
fn last(self) -> Option<<I as Iterator>::Item>
Sourceยงfn next_chunk<const N: usize>(
&mut self,
) -> Result<[Self::Item; N], IntoIter<Self::Item, N>>where
Self: Sized,
fn next_chunk<const N: usize>(
&mut self,
) -> Result<[Self::Item; N], IntoIter<Self::Item, N>>where
Self: Sized,
iter_next_chunk
)N
values. Read more1.0.0 ยท Sourceยงfn count(self) -> usizewhere
Self: Sized,
fn count(self) -> usizewhere
Self: Sized,
Sourceยงfn advance_by(&mut self, n: usize) -> Result<(), NonZero<usize>>
fn advance_by(&mut self, n: usize) -> Result<(), NonZero<usize>>
iter_advance_by
)n
elements. Read more1.28.0 ยท Sourceยงfn step_by(self, step: usize) -> StepBy<Self>where
Self: Sized,
fn step_by(self, step: usize) -> StepBy<Self>where
Self: Sized,
1.0.0 ยท Sourceยงfn chain<U>(self, other: U) -> Chain<Self, <U as IntoIterator>::IntoIter>
fn chain<U>(self, other: U) -> Chain<Self, <U as IntoIterator>::IntoIter>
1.0.0 ยท Sourceยงfn zip<U>(self, other: U) -> Zip<Self, <U as IntoIterator>::IntoIter>where
Self: Sized,
U: IntoIterator,
fn zip<U>(self, other: U) -> Zip<Self, <U as IntoIterator>::IntoIter>where
Self: Sized,
U: IntoIterator,
Sourceยงfn intersperse(self, separator: Self::Item) -> Intersperse<Self>
fn intersperse(self, separator: Self::Item) -> Intersperse<Self>
iter_intersperse
)separator
between adjacent
items of the original iterator. Read moreSourceยงfn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G>
fn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G>
iter_intersperse
)separator
between adjacent items of the original iterator. Read more1.0.0 ยท Sourceยงfn map<B, F>(self, f: F) -> Map<Self, F>
fn map<B, F>(self, f: F) -> Map<Self, F>
1.21.0 ยท Sourceยงfn for_each<F>(self, f: F)
fn for_each<F>(self, f: F)
1.0.0 ยท Sourceยงfn filter<P>(self, predicate: P) -> Filter<Self, P>
fn filter<P>(self, predicate: P) -> Filter<Self, P>
1.0.0 ยท Sourceยงfn filter_map<B, F>(self, f: F) -> FilterMap<Self, F>
fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F>
1.0.0 ยท Sourceยงfn enumerate(self) -> Enumerate<Self>where
Self: Sized,
fn enumerate(self) -> Enumerate<Self>where
Self: Sized,
1.0.0 ยท Sourceยงfn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P>
fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P>
1.0.0 ยท Sourceยงfn take_while<P>(self, predicate: P) -> TakeWhile<Self, P>
fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P>
1.57.0 ยท Sourceยงfn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P>
fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P>
1.0.0 ยท Sourceยงfn skip(self, n: usize) -> Skip<Self>where
Self: Sized,
fn skip(self, n: usize) -> Skip<Self>where
Self: Sized,
n
elements. Read more1.0.0 ยท Sourceยงfn take(self, n: usize) -> Take<Self>where
Self: Sized,
fn take(self, n: usize) -> Take<Self>where
Self: Sized,
n
elements, or fewer
if the underlying iterator ends sooner. Read more1.0.0 ยท Sourceยงfn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F>
fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F>
1.29.0 ยท Sourceยงfn flatten(self) -> Flatten<Self>
fn flatten(self) -> Flatten<Self>
Sourceยงfn map_windows<F, R, const N: usize>(self, f: F) -> MapWindows<Self, F, N>
fn map_windows<F, R, const N: usize>(self, f: F) -> MapWindows<Self, F, N>
iter_map_windows
)f
for each contiguous window of size N
over
self
and returns an iterator over the outputs of f
. Like slice::windows()
,
the windows during mapping overlap as well. Read more1.0.0 ยท Sourceยงfn inspect<F>(self, f: F) -> Inspect<Self, F>
fn inspect<F>(self, f: F) -> Inspect<Self, F>
1.0.0 ยท Sourceยงfn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
fn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
Sourceยงfn try_collect<B>(
&mut self,
) -> <<Self::Item as Try>::Residual as Residual<B>>::TryType
fn try_collect<B>( &mut self, ) -> <<Self::Item as Try>::Residual as Residual<B>>::TryType
iterator_try_collect
)Sourceยงfn collect_into<E>(self, collection: &mut E) -> &mut E
fn collect_into<E>(self, collection: &mut E) -> &mut E
iter_collect_into
)1.0.0 ยท Sourceยงfn partition<B, F>(self, f: F) -> (B, B)
fn partition<B, F>(self, f: F) -> (B, B)
Sourceยงfn partition_in_place<'a, T, P>(self, predicate: P) -> usize
fn partition_in_place<'a, T, P>(self, predicate: P) -> usize
iter_partition_in_place
)true
precede all those that return false
.
Returns the number of true
elements found. Read moreSourceยงfn is_partitioned<P>(self, predicate: P) -> bool
fn is_partitioned<P>(self, predicate: P) -> bool
iter_is_partitioned
)true
precede all those that return false
. Read more1.27.0 ยท Sourceยงfn try_fold<B, F, R>(&mut self, init: B, f: F) -> R
fn try_fold<B, F, R>(&mut self, init: B, f: F) -> R
1.27.0 ยท Sourceยงfn try_for_each<F, R>(&mut self, f: F) -> R
fn try_for_each<F, R>(&mut self, f: F) -> R
1.0.0 ยท Sourceยงfn fold<B, F>(self, init: B, f: F) -> B
fn fold<B, F>(self, init: B, f: F) -> B
1.51.0 ยท Sourceยงfn reduce<F>(self, f: F) -> Option<Self::Item>
fn reduce<F>(self, f: F) -> Option<Self::Item>
Sourceยงfn try_reduce<R>(
&mut self,
f: impl FnMut(Self::Item, Self::Item) -> R,
) -> <<R as Try>::Residual as Residual<Option<<R as Try>::Output>>>::TryType
fn try_reduce<R>( &mut self, f: impl FnMut(Self::Item, Self::Item) -> R, ) -> <<R as Try>::Residual as Residual<Option<<R as Try>::Output>>>::TryType
iterator_try_reduce
)1.0.0 ยท Sourceยงfn all<F>(&mut self, f: F) -> bool
fn all<F>(&mut self, f: F) -> bool
1.0.0 ยท Sourceยงfn any<F>(&mut self, f: F) -> bool
fn any<F>(&mut self, f: F) -> bool
1.0.0 ยท Sourceยงfn find<P>(&mut self, predicate: P) -> Option<Self::Item>
fn find<P>(&mut self, predicate: P) -> Option<Self::Item>
1.30.0 ยท Sourceยงfn find_map<B, F>(&mut self, f: F) -> Option<B>
fn find_map<B, F>(&mut self, f: F) -> Option<B>
Sourceยงfn try_find<R>(
&mut self,
f: impl FnMut(&Self::Item) -> R,
) -> <<R as Try>::Residual as Residual<Option<Self::Item>>>::TryType
fn try_find<R>( &mut self, f: impl FnMut(&Self::Item) -> R, ) -> <<R as Try>::Residual as Residual<Option<Self::Item>>>::TryType
try_find
)1.0.0 ยท Sourceยงfn position<P>(&mut self, predicate: P) -> Option<usize>
fn position<P>(&mut self, predicate: P) -> Option<usize>
1.0.0 ยท Sourceยงfn rposition<P>(&mut self, predicate: P) -> Option<usize>
fn rposition<P>(&mut self, predicate: P) -> Option<usize>
1.0.0 ยท Sourceยงfn max(self) -> Option<Self::Item>
fn max(self) -> Option<Self::Item>
1.0.0 ยท Sourceยงfn min(self) -> Option<Self::Item>
fn min(self) -> Option<Self::Item>
1.6.0 ยท Sourceยงfn max_by_key<B, F>(self, f: F) -> Option<Self::Item>
fn max_by_key<B, F>(self, f: F) -> Option<Self::Item>
1.15.0 ยท Sourceยงfn max_by<F>(self, compare: F) -> Option<Self::Item>
fn max_by<F>(self, compare: F) -> Option<Self::Item>
1.6.0 ยท Sourceยงfn min_by_key<B, F>(self, f: F) -> Option<Self::Item>
fn min_by_key<B, F>(self, f: F) -> Option<Self::Item>
1.15.0 ยท Sourceยงfn min_by<F>(self, compare: F) -> Option<Self::Item>
fn min_by<F>(self, compare: F) -> Option<Self::Item>
1.0.0 ยท Sourceยงfn rev(self) -> Rev<Self>where
Self: Sized + DoubleEndedIterator,
fn rev(self) -> Rev<Self>where
Self: Sized + DoubleEndedIterator,
1.0.0 ยท Sourceยงfn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB)
fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB)
1.36.0 ยท Sourceยงfn copied<'a, T>(self) -> Copied<Self>
fn copied<'a, T>(self) -> Copied<Self>
Sourceยงfn array_chunks<const N: usize>(self) -> ArrayChunks<Self, N>where
Self: Sized,
fn array_chunks<const N: usize>(self) -> ArrayChunks<Self, N>where
Self: Sized,
iter_array_chunks
)N
elements of the iterator at a time. Read more1.11.0 ยท Sourceยงfn product<P>(self) -> P
fn product<P>(self) -> P
Sourceยงfn cmp_by<I, F>(self, other: I, cmp: F) -> Ordering
fn cmp_by<I, F>(self, other: I, cmp: F) -> Ordering
iter_order_by
)Iterator
with those
of another with respect to the specified comparison function. Read more1.5.0 ยท Sourceยงfn partial_cmp<I>(self, other: I) -> Option<Ordering>
fn partial_cmp<I>(self, other: I) -> Option<Ordering>
PartialOrd
elements of
this Iterator
with those of another. The comparison works like short-circuit
evaluation, returning a result without comparing the remaining elements.
As soon as an order can be determined, the evaluation stops and a result is returned. Read moreSourceยงfn partial_cmp_by<I, F>(self, other: I, partial_cmp: F) -> Option<Ordering>where
Self: Sized,
I: IntoIterator,
F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Option<Ordering>,
fn partial_cmp_by<I, F>(self, other: I, partial_cmp: F) -> Option<Ordering>where
Self: Sized,
I: IntoIterator,
F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Option<Ordering>,
iter_order_by
)Iterator
with those
of another with respect to the specified comparison function. Read moreSourceยงfn eq_by<I, F>(self, other: I, eq: F) -> bool
fn eq_by<I, F>(self, other: I, eq: F) -> bool
iter_order_by
)1.5.0 ยท Sourceยงfn lt<I>(self, other: I) -> bool
fn lt<I>(self, other: I) -> bool
Iterator
are lexicographically
less than those of another. Read more1.5.0 ยท Sourceยงfn le<I>(self, other: I) -> bool
fn le<I>(self, other: I) -> bool
Iterator
are lexicographically
less or equal to those of another. Read more1.5.0 ยท Sourceยงfn gt<I>(self, other: I) -> bool
fn gt<I>(self, other: I) -> bool
Iterator
are lexicographically
greater than those of another. Read more1.5.0 ยท Sourceยงfn ge<I>(self, other: I) -> bool
fn ge<I>(self, other: I) -> bool
Iterator
are lexicographically
greater than or equal to those of another. Read more1.82.0 ยท Sourceยงfn is_sorted(self) -> bool
fn is_sorted(self) -> bool
1.82.0 ยท Sourceยงfn is_sorted_by<F>(self, compare: F) -> bool
fn is_sorted_by<F>(self, compare: F) -> bool
1.82.0 ยท Sourceยงfn is_sorted_by_key<F, K>(self, f: F) -> bool
fn is_sorted_by_key<F, K>(self, f: F) -> bool
1.0.0 ยท Sourceยงimpl<T, A> Ord for Box<T, A>
impl<T, A> Ord for Box<T, A>
1.21.0 ยท Sourceยงfn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere
Self: Sized,
1.0.0 ยท Sourceยงimpl<T, A> PartialOrd for Box<T, A>
impl<T, A> PartialOrd for Box<T, A>
1.0.0 ยท Sourceยงimpl<R> Read for Box<R>
impl<R> Read for Box<R>
Sourceยงfn read(&mut self, buf: &mut [u8]) -> Result<usize, Error>
fn read(&mut self, buf: &mut [u8]) -> Result<usize, Error>
Sourceยงfn read_buf(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>
fn read_buf(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>
read_buf
)Sourceยงfn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize, Error>
fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize, Error>
read
, except that it reads into a slice of buffers. Read moreSourceยงfn is_read_vectored(&self) -> bool
fn is_read_vectored(&self) -> bool
can_vector
)Sourceยงfn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize, Error>
fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize, Error>
buf
. Read moreSourceยงfn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>
fn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>
buf
. Read moreSourceยงfn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Error>
fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Error>
buf
. Read moreSourceยงfn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>
fn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>
read_buf
)cursor
. Read more1.0.0 ยท Sourceยงfn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
fn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
Read
. Read more1.0.0 ยท Sourceยงimpl<S> Seek for Box<S>
impl<S> Seek for Box<S>
Sourceยงfn seek(&mut self, pos: SeekFrom) -> Result<u64, Error>
fn seek(&mut self, pos: SeekFrom) -> Result<u64, Error>
Sourceยงfn stream_position(&mut self) -> Result<u64, Error>
fn stream_position(&mut self) -> Result<u64, Error>
1.55.0 ยท Sourceยงfn rewind(&mut self) -> Result<(), Error>
fn rewind(&mut self) -> Result<(), Error>
1.0.0 ยท Sourceยงimpl<W> Write for Box<W>
impl<W> Write for Box<W>
Sourceยงfn write(&mut self, buf: &[u8]) -> Result<usize, Error>
fn write(&mut self, buf: &[u8]) -> Result<usize, Error>
Sourceยงfn is_write_vectored(&self) -> bool
fn is_write_vectored(&self) -> bool
can_vector
)