pub type BoxError = Box<dyn Error + Send + Sync + 'static>;
Expand description
A boxed std::error::Error
.
Aliased Type§
struct BoxError(/* private fields */);
Implementations
source§impl<T> Box<T>where
T: ?Sized,
impl<T> Box<T>where
T: ?Sized,
1.4.0 · 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
.
§Safety
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.
§Examples
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>
🔬This 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
.
§Safety
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.
§Examples
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);
}
source§impl<T> Box<T>
impl<T> Box<T>
1.0.0 · 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 doesn’t actually allocate if T
is zero-sized.
§Examples
let five = Box::new(5);
1.82.0 · sourcepub fn new_uninit() -> Box<MaybeUninit<T>>
pub fn new_uninit() -> Box<MaybeUninit<T>>
Constructs a new box with uninitialized contents.
§Examples
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>>
🔬This 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.
§Examples
#![feature(new_zeroed_alloc)]
let zero = Box::<u32>::new_zeroed();
let zero = unsafe { zero.assume_init() };
assert_eq!(*zero, 0)
1.33.0 · 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>
🔬This 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 doesn’t actually allocate if T
is zero-sized.
§Examples
#![feature(allocator_api)]
let five = Box::try_new(5)?;
sourcepub fn try_new_uninit() -> Result<Box<MaybeUninit<T>>, AllocError>
🔬This 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
§Examples
#![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>
🔬This 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.
§Examples
#![feature(allocator_api)]
let zero = Box::<u32>::try_new_zeroed()?;
let zero = unsafe { zero.assume_init() };
assert_eq!(*zero, 0);
source§impl<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>
🔬This 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
.
§Safety
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
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>
🔬This 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
.
§Safety
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
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 · 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.
§Examples
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>
🔬This 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.
§Examples
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)
🔬This 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.
§Examples
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)
🔬This 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.
§Examples
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
🔬This 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
’s 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.
§Examples
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
🔬This 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
’s 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.
§Examples
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
🔬This 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 · 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 program’s 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.
§Examples
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) · 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
.
§Notes
It’s not recommended that crates add an impl like From<Box<T>> for Pin<T>
,
as it’ll 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);
source§impl<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,
🔬This 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 doesn’t actually allocate if T
is zero-sized.
§Examples
#![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,
🔬This 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 doesn’t actually allocate if T
is zero-sized.
§Examples
#![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,
🔬This 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.
§Examples
#![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,
🔬This 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
§Examples
#![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,
🔬This 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.
§Examples
#![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,
🔬This 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.
§Examples
#![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,
🔬This 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>
🔬This 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
🔬This 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.
§Examples
#![feature(box_into_inner)]
let c = Box::new(5);
assert_eq!(Box::into_inner(c), 5);
Trait Implementations
§impl<A> Arbitrary for Box<A>where
A: Arbitrary,
impl<A> Arbitrary for Box<A>where
A: Arbitrary,
§type Parameters = <A as Arbitrary>::Parameters
type Parameters = <A as Arbitrary>::Parameters
arbitrary_with
accepts for configuration
of the generated Strategy
. Parameters must implement Default
.§type Strategy = MapInto<<A as Arbitrary>::Strategy, Box<A>>
type Strategy = MapInto<<A as Arbitrary>::Strategy, Box<A>>
Strategy
used to generate values of type Self
.§fn arbitrary_with(
args: <Box<A> as Arbitrary>::Parameters,
) -> <Box<A> as Arbitrary>::Strategy
fn arbitrary_with( args: <Box<A> as Arbitrary>::Parameters, ) -> <Box<A> as Arbitrary>::Strategy
§impl<A> ArbitraryF1<A> for Box<A>where
A: Debug + 'static,
impl<A> ArbitraryF1<A> for Box<A>where
A: Debug + 'static,
§type Parameters = ()
type Parameters = ()
lift1_with
accepts for
configuration of the lifted and generated Strategy
. Parameters
must implement Default
.§fn lift1_with<S>(
base: S,
_args: <Box<A> as ArbitraryF1<A>>::Parameters,
) -> BoxedStrategy<Box<A>>where
S: Strategy<Value = A> + 'static,
fn lift1_with<S>(
base: S,
_args: <Box<A> as ArbitraryF1<A>>::Parameters,
) -> BoxedStrategy<Box<A>>where
S: Strategy<Value = A> + 'static,
1.64.0 · source§impl<T> AsFd for Box<T>
impl<T> AsFd for Box<T>
source§fn as_fd(&self) -> BorrowedFd<'_>
fn as_fd(&self) -> BorrowedFd<'_>
§impl<T> AsyncBufRead for Box<T>
impl<T> AsyncBufRead for Box<T>
§impl<T> AsyncBufRead for Box<T>
impl<T> AsyncBufRead for Box<T>
source§impl<Args, F, A> AsyncFn<Args> for Box<F, A>
impl<Args, F, A> AsyncFn<Args> for Box<F, A>
source§extern "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.source§impl<Args, F, A> AsyncFnMut<Args> for Box<F, A>
impl<Args, F, A> AsyncFnMut<Args> for Box<F, A>
source§type 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
.source§extern "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.source§impl<Args, F, A> AsyncFnOnce<Args> for Box<F, A>
impl<Args, F, A> AsyncFnOnce<Args> for Box<F, A>
source§type Output = <F as AsyncFnOnce<Args>>::Output
type Output = <F as AsyncFnOnce<Args>>::Output
async_fn_traits
)source§type CallOnceFuture = <F as AsyncFnOnce<Args>>::CallOnceFuture
type CallOnceFuture = <F as AsyncFnOnce<Args>>::CallOnceFuture
async_fn_traits
)AsyncFnOnce::async_call_once
.source§extern "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.source§impl<S> AsyncIterator for Box<S>
impl<S> AsyncIterator for Box<S>
source§type Item = <S as AsyncIterator>::Item
type Item = <S as AsyncIterator>::Item
async_iterator
)source§fn 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 more§impl<T> AsyncRead for Box<T>
impl<T> AsyncRead for Box<T>
§impl<T> AsyncWrite for Box<T>
impl<T> AsyncWrite for Box<T>
§fn poll_write(
self: Pin<&mut Box<T>>,
cx: &mut Context<'_>,
buf: &[u8],
) -> Poll<Result<usize, Error>>
fn poll_write( self: Pin<&mut Box<T>>, cx: &mut Context<'_>, buf: &[u8], ) -> Poll<Result<usize, Error>>
buf
into the object. Read more§fn poll_write_vectored(
self: Pin<&mut Box<T>>,
cx: &mut Context<'_>,
bufs: &[IoSlice<'_>],
) -> Poll<Result<usize, Error>>
fn poll_write_vectored( self: Pin<&mut Box<T>>, cx: &mut Context<'_>, bufs: &[IoSlice<'_>], ) -> Poll<Result<usize, Error>>
bufs
into the object using vectored
IO operations. Read more§impl<T> AsyncWrite for Box<T>
impl<T> AsyncWrite for Box<T>
§fn poll_write(
self: Pin<&mut Box<T>>,
cx: &mut Context<'_>,
buf: &[u8],
) -> Poll<Result<usize, Error>>
fn poll_write( self: Pin<&mut Box<T>>, cx: &mut Context<'_>, buf: &[u8], ) -> Poll<Result<usize, Error>>
buf
into the object. Read more§fn poll_write_vectored(
self: Pin<&mut Box<T>>,
cx: &mut Context<'_>,
bufs: &[IoSlice<'_>],
) -> Poll<Result<usize, Error>>
fn poll_write_vectored( self: Pin<&mut Box<T>>, cx: &mut Context<'_>, bufs: &[IoSlice<'_>], ) -> Poll<Result<usize, Error>>
poll_write
, except that it writes from a slice of buffers. Read more§fn is_write_vectored(&self) -> bool
fn is_write_vectored(&self) -> bool
poll_write_vectored
implementation. Read more§impl<T> Body for Box<T>
impl<T> Body for Box<T>
1.1.0 · source§impl<T, A> BorrowMut<T> for Box<T, A>
impl<T, A> BorrowMut<T> for Box<T, A>
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
§impl<T> Buf for Box<T>where
T: Buf + ?Sized,
impl<T> Buf for Box<T>where
T: Buf + ?Sized,
§fn remaining(&self) -> usize
fn remaining(&self) -> usize
§fn chunk(&self) -> &[u8] ⓘ
fn chunk(&self) -> &[u8] ⓘ
Buf::remaining()
. Note that this can return a shorter slice (this
allows non-continuous internal representation). Read more§fn chunks_vectored<'b>(&'b self, dst: &mut [IoSlice<'b>]) -> usize
fn chunks_vectored<'b>(&'b self, dst: &mut [IoSlice<'b>]) -> usize
§fn has_remaining(&self) -> bool
fn has_remaining(&self) -> bool
§fn copy_to_slice(&mut self, dst: &mut [u8])
fn copy_to_slice(&mut self, dst: &mut [u8])
§fn get_u16(&mut self) -> u16
fn get_u16(&mut self) -> u16
self
in big-endian byte order. Read more§fn get_u16_le(&mut self) -> u16
fn get_u16_le(&mut self) -> u16
self
in little-endian byte order. Read more§fn get_u16_ne(&mut self) -> u16
fn get_u16_ne(&mut self) -> u16
self
in native-endian byte order. Read more§fn get_i16(&mut self) -> i16
fn get_i16(&mut self) -> i16
self
in big-endian byte order. Read more§fn get_i16_le(&mut self) -> i16
fn get_i16_le(&mut self) -> i16
self
in little-endian byte order. Read more§fn get_i16_ne(&mut self) -> i16
fn get_i16_ne(&mut self) -> i16
self
in native-endian byte order. Read more§fn get_u32(&mut self) -> u32
fn get_u32(&mut self) -> u32
self
in the big-endian byte order. Read more§fn get_u32_le(&mut self) -> u32
fn get_u32_le(&mut self) -> u32
self
in the little-endian byte order. Read more§fn get_u32_ne(&mut self) -> u32
fn get_u32_ne(&mut self) -> u32
self
in native-endian byte order. Read more§fn get_i32(&mut self) -> i32
fn get_i32(&mut self) -> i32
self
in big-endian byte order. Read more§fn get_i32_le(&mut self) -> i32
fn get_i32_le(&mut self) -> i32
self
in little-endian byte order. Read more§fn get_i32_ne(&mut self) -> i32
fn get_i32_ne(&mut self) -> i32
self
in native-endian byte order. Read more§fn get_u64(&mut self) -> u64
fn get_u64(&mut self) -> u64
self
in big-endian byte order. Read more§fn get_u64_le(&mut self) -> u64
fn get_u64_le(&mut self) -> u64
self
in little-endian byte order. Read more§fn get_u64_ne(&mut self) -> u64
fn get_u64_ne(&mut self) -> u64
self
in native-endian byte order. Read more§fn get_i64(&mut self) -> i64
fn get_i64(&mut self) -> i64
self
in big-endian byte order. Read more§fn get_i64_le(&mut self) -> i64
fn get_i64_le(&mut self) -> i64
self
in little-endian byte order. Read more§fn get_i64_ne(&mut self) -> i64
fn get_i64_ne(&mut self) -> i64
self
in native-endian byte order. Read more§fn get_uint(&mut self, nbytes: usize) -> u64
fn get_uint(&mut self, nbytes: usize) -> u64
self
in big-endian byte order. Read more§fn get_uint_le(&mut self, nbytes: usize) -> u64
fn get_uint_le(&mut self, nbytes: usize) -> u64
self
in little-endian byte order. Read more§fn get_uint_ne(&mut self, nbytes: usize) -> u64
fn get_uint_ne(&mut self, nbytes: usize) -> u64
self
in native-endian byte order. Read more§fn get_int(&mut self, nbytes: usize) -> i64
fn get_int(&mut self, nbytes: usize) -> i64
self
in big-endian byte order. Read more§fn get_int_le(&mut self, nbytes: usize) -> i64
fn get_int_le(&mut self, nbytes: usize) -> i64
self
in little-endian byte order. Read more§fn get_int_ne(&mut self, nbytes: usize) -> i64
fn get_int_ne(&mut self, nbytes: usize) -> i64
self
in native-endian byte order. Read more§fn copy_to_bytes(&mut self, len: usize) -> Bytes
fn copy_to_bytes(&mut self, len: usize) -> Bytes
§fn get_u128(&mut self) -> u128
fn get_u128(&mut self) -> u128
self
in big-endian byte order. Read more§fn get_u128_le(&mut self) -> u128
fn get_u128_le(&mut self) -> u128
self
in little-endian byte order. Read more§fn get_u128_ne(&mut self) -> u128
fn get_u128_ne(&mut self) -> u128
self
in native-endian byte order. Read more§fn get_i128(&mut self) -> i128
fn get_i128(&mut self) -> i128
self
in big-endian byte order. Read more§fn get_i128_le(&mut self) -> i128
fn get_i128_le(&mut self) -> i128
self
in little-endian byte order. Read more§fn get_i128_ne(&mut self) -> i128
fn get_i128_ne(&mut self) -> i128
self
in native-endian byte order. Read more§fn get_f32(&mut self) -> f32
fn get_f32(&mut self) -> f32
self
in big-endian byte order. Read more§fn get_f32_le(&mut self) -> f32
fn get_f32_le(&mut self) -> f32
self
in little-endian byte order. Read more§fn get_f32_ne(&mut self) -> f32
fn get_f32_ne(&mut self) -> f32
self
in native-endian byte order. Read more§fn get_f64(&mut self) -> f64
fn get_f64(&mut self) -> f64
self
in big-endian byte order. Read more§fn get_f64_le(&mut self) -> f64
fn get_f64_le(&mut self) -> f64
self
in little-endian byte order. Read more§fn get_f64_ne(&mut self) -> f64
fn get_f64_ne(&mut self) -> f64
self
in native-endian byte order. Read more§impl<T> BufMut for Box<T>where
T: BufMut + ?Sized,
impl<T> BufMut for Box<T>where
T: BufMut + ?Sized,
§fn remaining_mut(&self) -> usize
fn remaining_mut(&self) -> usize
§fn chunk_mut(&mut self) -> &mut UninitSlice
fn chunk_mut(&mut self) -> &mut UninitSlice
BufMut::remaining_mut()
. Note that this can be shorter than the
whole remainder of the buffer (this allows non-continuous implementation). Read more§unsafe fn advance_mut(&mut self, cnt: usize)
unsafe fn advance_mut(&mut self, cnt: usize)
§fn put_u16(&mut self, n: u16)
fn put_u16(&mut self, n: u16)
self
in big-endian byte order. Read more§fn put_u16_le(&mut self, n: u16)
fn put_u16_le(&mut self, n: u16)
self
in little-endian byte order. Read more§fn put_u16_ne(&mut self, n: u16)
fn put_u16_ne(&mut self, n: u16)
self
in native-endian byte order. Read more§fn put_i16(&mut self, n: i16)
fn put_i16(&mut self, n: i16)
self
in big-endian byte order. Read more§fn put_i16_le(&mut self, n: i16)
fn put_i16_le(&mut self, n: i16)
self
in little-endian byte order. Read more§fn put_i16_ne(&mut self, n: i16)
fn put_i16_ne(&mut self, n: i16)
self
in native-endian byte order. Read more§fn put_u32(&mut self, n: u32)
fn put_u32(&mut self, n: u32)
self
in big-endian byte order. Read more§fn put_u32_le(&mut self, n: u32)
fn put_u32_le(&mut self, n: u32)
self
in little-endian byte order. Read more§fn put_u32_ne(&mut self, n: u32)
fn put_u32_ne(&mut self, n: u32)
self
in native-endian byte order. Read more§fn put_i32(&mut self, n: i32)
fn put_i32(&mut self, n: i32)
self
in big-endian byte order. Read more§fn put_i32_le(&mut self, n: i32)
fn put_i32_le(&mut self, n: i32)
self
in little-endian byte order. Read more§fn put_i32_ne(&mut self, n: i32)
fn put_i32_ne(&mut self, n: i32)
self
in native-endian byte order. Read more§fn put_u64(&mut self, n: u64)
fn put_u64(&mut self, n: u64)
self
in the big-endian byte order. Read more§fn put_u64_le(&mut self, n: u64)
fn put_u64_le(&mut self, n: u64)
self
in little-endian byte order. Read more§fn put_u64_ne(&mut self, n: u64)
fn put_u64_ne(&mut self, n: u64)
self
in native-endian byte order. Read more§fn put_i64(&mut self, n: i64)
fn put_i64(&mut self, n: i64)
self
in the big-endian byte order. Read more§fn put_i64_le(&mut self, n: i64)
fn put_i64_le(&mut self, n: i64)
self
in little-endian byte order. Read more§fn put_i64_ne(&mut self, n: i64)
fn put_i64_ne(&mut self, n: i64)
self
in native-endian byte order. Read more§fn has_remaining_mut(&self) -> bool
fn has_remaining_mut(&self) -> bool
self
for more bytes. Read more§fn put_u128(&mut self, n: u128)
fn put_u128(&mut self, n: u128)
self
in the big-endian byte order. Read more§fn put_u128_le(&mut self, n: u128)
fn put_u128_le(&mut self, n: u128)
self
in little-endian byte order. Read more§fn put_u128_ne(&mut self, n: u128)
fn put_u128_ne(&mut self, n: u128)
self
in native-endian byte order. Read more§fn put_i128(&mut self, n: i128)
fn put_i128(&mut self, n: i128)
self
in the big-endian byte order. Read more§fn put_i128_le(&mut self, n: i128)
fn put_i128_le(&mut self, n: i128)
self
in little-endian byte order. Read more§fn put_i128_ne(&mut self, n: i128)
fn put_i128_ne(&mut self, n: i128)
self
in native-endian byte order. Read more§fn put_uint(&mut self, n: u64, nbytes: usize)
fn put_uint(&mut self, n: u64, nbytes: usize)
self
in big-endian byte order. Read more§fn put_uint_le(&mut self, n: u64, nbytes: usize)
fn put_uint_le(&mut self, n: u64, nbytes: usize)
self
in the little-endian byte order. Read more§fn put_uint_ne(&mut self, n: u64, nbytes: usize)
fn put_uint_ne(&mut self, n: u64, nbytes: usize)
self
in the native-endian byte order. Read more§fn put_int_le(&mut self, n: i64, nbytes: usize)
fn put_int_le(&mut self, n: i64, nbytes: usize)
§fn put_int_ne(&mut self, n: i64, nbytes: usize)
fn put_int_ne(&mut self, n: i64, nbytes: usize)
§fn put_f32(&mut self, n: f32)
fn put_f32(&mut self, n: f32)
self
in big-endian byte order. Read more§fn put_f32_le(&mut self, n: f32)
fn put_f32_le(&mut self, n: f32)
self
in little-endian byte order. Read more§fn put_f32_ne(&mut self, n: f32)
fn put_f32_ne(&mut self, n: f32)
self
in native-endian byte order. Read more§fn put_f64(&mut self, n: f64)
fn put_f64(&mut self, n: f64)
self
in big-endian byte order. Read more§fn put_f64_le(&mut self, n: f64)
fn put_f64_le(&mut self, n: f64)
self
in little-endian byte order. Read more§fn put_f64_ne(&mut self, n: f64)
fn put_f64_ne(&mut self, n: f64)
self
in native-endian byte order. Read more1.0.0 · source§impl<B> BufRead for Box<B>
impl<B> BufRead for Box<B>
source§fn fill_buf(&mut self) -> Result<&[u8], Error>
fn fill_buf(&mut self) -> Result<&[u8], Error>
source§fn 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 moresource§fn 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 moresource§fn 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 · source§fn 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 · source§impl<T, A> Clone for Box<T, A>
impl<T, A> Clone for Box<T, A>
source§fn clone(&self) -> Box<T, A>
fn clone(&self) -> Box<T, A>
Returns a new box with a clone()
of this box’s contents.
§Examples
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);
source§fn clone_from(&mut self, source: &Box<T, A>)
fn clone_from(&mut self, source: &Box<T, A>)
Copies source
’s contents into self
without creating a new allocation.
§Examples
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);
source§impl<G, R, A> Coroutine<R> for Box<G, A>
impl<G, R, A> Coroutine<R> for Box<G, A>
source§type Yield = <G as Coroutine<R>>::Yield
type Yield = <G as Coroutine<R>>::Yield
coroutine_trait
)source§impl<S> DebugSecret for Box<S>where
S: DebugSecret + Zeroize,
impl<S> DebugSecret for Box<S>where
S: DebugSecret + Zeroize,
source§impl<'de, T> Deserialize<'de> for Box<T>where
T: Deserialize<'de>,
impl<'de, T> Deserialize<'de> for Box<T>where
T: Deserialize<'de>,
source§fn deserialize<D>(
deserializer: D,
) -> Result<Box<T>, <D as Deserializer<'de>>::Error>where
D: Deserializer<'de>,
fn deserialize<D>(
deserializer: D,
) -> Result<Box<T>, <D as Deserializer<'de>>::Error>where
D: Deserializer<'de>,
source§impl<'de, T, U> DeserializeAs<'de, Box<T>> for Box<U>where
U: DeserializeAs<'de, T>,
impl<'de, T, U> DeserializeAs<'de, Box<T>> for Box<U>where
U: DeserializeAs<'de, T>,
source§fn deserialize_as<D>(
deserializer: D,
) -> Result<Box<T>, <D as Deserializer<'de>>::Error>where
D: Deserializer<'de>,
fn deserialize_as<D>(
deserializer: D,
) -> Result<Box<T>, <D as Deserializer<'de>>::Error>where
D: Deserializer<'de>,
1.0.0 · source§impl<I, A> DoubleEndedIterator for Box<I, A>
impl<I, A> DoubleEndedIterator for Box<I, A>
source§fn next_back(&mut self) -> Option<<I as Iterator>::Item>
fn next_back(&mut self) -> Option<<I as Iterator>::Item>
source§fn 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 moresource§fn 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 · source§fn 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 more§impl<T> DynamicUsage for Box<T>where
T: DynamicUsage,
impl<T> DynamicUsage for Box<T>where
T: DynamicUsage,
§fn dynamic_usage(&self) -> usize
fn dynamic_usage(&self) -> usize
1.8.0 · source§impl<T> Error for Box<T>where
T: Error,
impl<T> Error for Box<T>where
T: Error,
source§fn description(&self) -> &str
fn description(&self) -> &str
source§fn cause(&self) -> Option<&dyn Error>
fn cause(&self) -> Option<&dyn Error>
1.0.0 · source§impl<I, A> ExactSizeIterator for Box<I, A>
impl<I, A> ExactSizeIterator for Box<I, A>
1.6.0 · source§impl<'a> From<&str> for Box<dyn Error + 'a>
impl<'a> From<&str> for Box<dyn Error + 'a>
1.0.0 · source§impl<'a> From<&str> for Box<dyn Error + Sync + Send + 'a>
impl<'a> From<&str> for Box<dyn Error + Sync + Send + 'a>
1.22.0 · source§impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + 'a>
impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + 'a>
1.22.0 · source§impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + Sync + Send + 'a>
impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + Sync + Send + 'a>
source§fn from(err: Cow<'b, str>) -> Box<dyn Error + Sync + Send + 'a>
fn from(err: Cow<'b, str>) -> Box<dyn Error + Sync + Send + 'a>
Converts a Cow
into a box of dyn Error
+ Send
+ Sync
.
§Examples
use std::error::Error;
use std::mem;
use std::borrow::Cow;
let a_cow_str_error = Cow::from("a str error");
let a_boxed_error = Box::<dyn Error + Send + Sync>::from(a_cow_str_error);
assert!(
mem::size_of::<Box<dyn Error + Send + Sync>>() == mem::size_of_val(&a_boxed_error))
1.0.0 · source§impl<'a, E> From<E> for Box<dyn Error + 'a>where
E: Error + 'a,
impl<'a, E> From<E> for Box<dyn Error + 'a>where
E: Error + 'a,
source§fn from(err: E) -> Box<dyn Error + 'a>
fn from(err: E) -> Box<dyn Error + 'a>
Converts a type of Error
into a box of dyn Error
.
§Examples
use std::error::Error;
use std::fmt;
use std::mem;
#[derive(Debug)]
struct AnError;
impl fmt::Display for AnError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "An error")
}
}
impl Error for AnError {}
let an_error = AnError;
assert!(0 == mem::size_of_val(&an_error));
let a_boxed_error = Box::<dyn Error>::from(an_error);
assert!(mem::size_of::<Box<dyn Error>>() == mem::size_of_val(&a_boxed_error))
1.0.0 · source§impl<'a, E> From<E> for Box<dyn Error + Sync + Send + 'a>
impl<'a, E> From<E> for Box<dyn Error + Sync + Send + 'a>
source§fn from(err: E) -> Box<dyn Error + Sync + Send + 'a>
fn from(err: E) -> Box<dyn Error + Sync + Send + 'a>
Converts a type of Error
+ Send
+ Sync
into a box of
dyn Error
+ Send
+ Sync
.
§Examples
use std::error::Error;
use std::fmt;
use std::mem;
#[derive(Debug)]
struct AnError;
impl fmt::Display for AnError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "An error")
}
}
impl Error for AnError {}
unsafe impl Send for AnError {}
unsafe impl Sync for AnError {}
let an_error = AnError;
assert!(0 == mem::size_of_val(&an_error));
let a_boxed_error = Box::<dyn Error + Send + Sync>::from(an_error);
assert!(
mem::size_of::<Box<dyn Error + Send + Sync>>() == mem::size_of_val(&a_boxed_error))
1.6.0 · source§impl<'a> From<String> for Box<dyn Error + 'a>
impl<'a> From<String> for Box<dyn Error + 'a>
1.0.0 · source§impl<'a> From<String> for Box<dyn Error + Sync + Send + 'a>
impl<'a> From<String> for Box<dyn Error + Sync + Send + 'a>
source§fn from(err: String) -> Box<dyn Error + Sync + Send + 'a>
fn from(err: String) -> Box<dyn Error + Sync + Send + 'a>
Converts a String
into a box of dyn Error
+ Send
+ Sync
.
§Examples
use std::error::Error;
use std::mem;
let a_string_error = "a string error".to_string();
let a_boxed_error = Box::<dyn Error + Send + Sync>::from(a_string_error);
assert!(
mem::size_of::<Box<dyn Error + Send + Sync>>() == mem::size_of_val(&a_boxed_error))
§impl<F> FusedFuture for Box<F>
impl<F> FusedFuture for Box<F>
§fn is_terminated(&self) -> bool
fn is_terminated(&self) -> bool
true
if the underlying future should no longer be polled.§impl<S> FusedStream for Box<S>
impl<S> FusedStream for Box<S>
§fn is_terminated(&self) -> bool
fn is_terminated(&self) -> bool
true
if the stream should no longer be polled.1.22.0 · source§impl<T, A> Hasher for Box<T, A>
impl<T, A> Hasher for Box<T, A>
source§fn write_u128(&mut self, i: u128)
fn write_u128(&mut self, i: u128)
u128
into this hasher.source§fn write_usize(&mut self, i: usize)
fn write_usize(&mut self, i: usize)
usize
into this hasher.source§fn write_i128(&mut self, i: i128)
fn write_i128(&mut self, i: i128)
i128
into this hasher.source§fn write_isize(&mut self, i: isize)
fn write_isize(&mut self, i: isize)
isize
into this hasher.source§fn write_length_prefix(&mut self, len: usize)
fn write_length_prefix(&mut self, len: usize)
hasher_prefixfree_extras
)1.0.0 · source§impl<I, A> Iterator for Box<I, A>
impl<I, A> Iterator for Box<I, A>
source§fn next(&mut self) -> Option<<I as Iterator>::Item>
fn next(&mut self) -> Option<<I as Iterator>::Item>
source§fn size_hint(&self) -> (usize, Option<usize>)
fn size_hint(&self) -> (usize, Option<usize>)
source§fn 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 moresource§fn last(self) -> Option<<I as Iterator>::Item>
fn last(self) -> Option<<I as Iterator>::Item>
source§fn 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 · source§fn count(self) -> usizewhere
Self: Sized,
fn count(self) -> usizewhere
Self: Sized,
source§fn 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 · source§fn step_by(self, step: usize) -> StepBy<Self>where
Self: Sized,
fn step_by(self, step: usize) -> StepBy<Self>where
Self: Sized,
1.0.0 · source§fn 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 · source§fn 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,
source§fn 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 · source§fn map<B, F>(self, f: F) -> Map<Self, F>
fn map<B, F>(self, f: F) -> Map<Self, F>
1.0.0 · source§fn filter<P>(self, predicate: P) -> Filter<Self, P>
fn filter<P>(self, predicate: P) -> Filter<Self, P>
1.0.0 · source§fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F>
fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F>
1.0.0 · source§fn enumerate(self) -> Enumerate<Self>where
Self: Sized,
fn enumerate(self) -> Enumerate<Self>where
Self: Sized,
1.0.0 · source§fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P>
fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P>
1.0.0 · source§fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P>
fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P>
1.57.0 · source§fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P>
fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P>
1.0.0 · source§fn 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 · source§fn 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 · source§fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F>
fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F>
source§fn 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 · source§fn inspect<F>(self, f: F) -> Inspect<Self, F>
fn inspect<F>(self, f: F) -> Inspect<Self, F>
1.0.0 · source§fn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
fn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
source§fn 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 · source§fn partition<B, F>(self, f: F) -> (B, B)
fn partition<B, F>(self, f: F) -> (B, B)
source§fn 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 · source§fn 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 · source§fn try_for_each<F, R>(&mut self, f: F) -> R
fn try_for_each<F, R>(&mut self, f: F) -> R
1.0.0 · source§fn fold<B, F>(self, init: B, f: F) -> B
fn fold<B, F>(self, init: B, f: F) -> B
1.51.0 · source§fn reduce<F>(self, f: F) -> Option<Self::Item>
fn reduce<F>(self, f: F) -> Option<Self::Item>
source§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
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 · source§fn all<F>(&mut self, f: F) -> bool
fn all<F>(&mut self, f: F) -> bool
1.0.0 · source§fn any<F>(&mut self, f: F) -> bool
fn any<F>(&mut self, f: F) -> bool
1.0.0 · source§fn find<P>(&mut self, predicate: P) -> Option<Self::Item>
fn find<P>(&mut self, predicate: P) -> Option<Self::Item>
1.30.0 · source§fn find_map<B, F>(&mut self, f: F) -> Option<B>
fn find_map<B, F>(&mut self, f: F) -> Option<B>
source§fn 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 · source§fn position<P>(&mut self, predicate: P) -> Option<usize>
fn position<P>(&mut self, predicate: P) -> Option<usize>
1.6.0 · source§fn 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 · source§fn max_by<F>(self, compare: F) -> Option<Self::Item>
fn max_by<F>(self, compare: F) -> Option<Self::Item>
1.6.0 · source§fn 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 · source§fn min_by<F>(self, compare: F) -> Option<Self::Item>
fn min_by<F>(self, compare: F) -> Option<Self::Item>
1.0.0 · source§fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB)
fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB)
1.36.0 · source§fn copied<'a, T>(self) -> Copied<Self>
fn copied<'a, T>(self) -> Copied<Self>
source§fn 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 · source§fn product<P>(self) -> P
fn product<P>(self) -> P
source§fn 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 · source§fn 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 moresource§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>,
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 moresource§fn 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 · source§fn 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 · source§fn 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 · source§fn 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 · source§fn 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 · source§fn is_sorted_by<F>(self, compare: F) -> bool
fn is_sorted_by<F>(self, compare: F) -> bool
1.82.0 · source§fn is_sorted_by_key<F, K>(self, f: F) -> bool
fn is_sorted_by_key<F, K>(self, f: F) -> bool
§impl<L, S> Layer<S> for Box<L>where
L: Layer<S>,
S: Subscriber,
impl<L, S> Layer<S> for Box<L>where
L: Layer<S>,
S: Subscriber,
§fn on_register_dispatch(&self, subscriber: &Dispatch)
fn on_register_dispatch(&self, subscriber: &Dispatch)
Subscriber
. Read more§fn on_new_span(&self, attrs: &Attributes<'_>, id: &Id, ctx: Context<'_, S>)
fn on_new_span(&self, attrs: &Attributes<'_>, id: &Id, ctx: Context<'_, S>)
Attributes
and Id
.§fn register_callsite(&self, metadata: &'static Metadata<'static>) -> Interest
fn register_callsite(&self, metadata: &'static Metadata<'static>) -> Interest
Subscriber::register_callsite
. Read more§fn enabled(&self, metadata: &Metadata<'_>, ctx: Context<'_, S>) -> bool
fn enabled(&self, metadata: &Metadata<'_>, ctx: Context<'_, S>) -> bool
true
if this layer is interested in a span or event with the
given metadata
in the current [Context
], similarly to
Subscriber::enabled
. Read more§fn on_record(&self, span: &Id, values: &Record<'_>, ctx: Context<'_, S>)
fn on_record(&self, span: &Id, values: &Record<'_>, ctx: Context<'_, S>)
Id
recorded the given
values
.§fn on_follows_from(&self, span: &Id, follows: &Id, ctx: Context<'_, S>)
fn on_follows_from(&self, span: &Id, follows: &Id, ctx: Context<'_, S>)
span
recorded that it
follows from the span with the ID follows
.§fn event_enabled(&self, event: &Event<'_>, ctx: Context<'_, S>) -> bool
fn event_enabled(&self, event: &Event<'_>, ctx: Context<'_, S>) -> bool
§fn on_event(&self, event: &Event<'_>, ctx: Context<'_, S>)
fn on_event(&self, event: &Event<'_>, ctx: Context<'_, S>)
§fn on_enter(&self, id: &Id, ctx: Context<'_, S>)
fn on_enter(&self, id: &Id, ctx: Context<'_, S>)
§fn on_exit(&self, id: &Id, ctx: Context<'_, S>)
fn on_exit(&self, id: &Id, ctx: Context<'_, S>)
§fn on_close(&self, id: Id, ctx: Context<'_, S>)
fn on_close(&self, id: Id, ctx: Context<'_, S>)
§fn on_id_change(&self, old: &Id, new: &Id, ctx: Context<'_, S>)
fn on_id_change(&self, old: &Id, new: &Id, ctx: Context<'_, S>)
§fn and_then<L>(self, layer: L) -> Layered<L, Self, S>where
L: Layer<S>,
Self: Sized,
fn and_then<L>(self, layer: L) -> Layered<L, Self, S>where
L: Layer<S>,
Self: Sized,
Layer
, returning a Layered
struct implementing Layer
. Read more§fn with_subscriber(self, inner: S) -> Layered<Self, S>where
Self: Sized,
fn with_subscriber(self, inner: S) -> Layered<Self, S>where
Self: Sized,
Layer
with the given Subscriber
, returning a
Layered
struct that implements Subscriber
. Read more§fn with_filter<F>(self, filter: F) -> Filtered<Self, F, S>where
Self: Sized,
F: Filter<S>,
fn with_filter<F>(self, filter: F) -> Filtered<Self, F, S>where
Self: Sized,
F: Filter<S>,
source§impl<M> Message for Box<M>where
M: Message,
impl<M> Message for Box<M>where
M: Message,
source§fn encoded_len(&self) -> usize
fn encoded_len(&self) -> usize
source§fn encode(&self, buf: &mut impl BufMut) -> Result<(), EncodeError>where
Self: Sized,
fn encode(&self, buf: &mut impl BufMut) -> Result<(), EncodeError>where
Self: Sized,
source§fn encode_to_vec(&self) -> Vec<u8> ⓘwhere
Self: Sized,
fn encode_to_vec(&self) -> Vec<u8> ⓘwhere
Self: Sized,
source§fn encode_length_delimited(
&self,
buf: &mut impl BufMut,
) -> Result<(), EncodeError>where
Self: Sized,
fn encode_length_delimited(
&self,
buf: &mut impl BufMut,
) -> Result<(), EncodeError>where
Self: Sized,
source§fn encode_length_delimited_to_vec(&self) -> Vec<u8> ⓘwhere
Self: Sized,
fn encode_length_delimited_to_vec(&self) -> Vec<u8> ⓘwhere
Self: Sized,
source§fn merge(&mut self, buf: impl Buf) -> Result<(), DecodeError>where
Self: Sized,
fn merge(&mut self, buf: impl Buf) -> Result<(), DecodeError>where
Self: Sized,
self
. Read moresource§fn merge_length_delimited(&mut self, buf: impl Buf) -> Result<(), DecodeError>where
Self: Sized,
fn merge_length_delimited(&mut self, buf: impl Buf) -> Result<(), DecodeError>where
Self: Sized,
self
.1.0.0 · source§impl<T, A> Ord for Box<T, A>
impl<T, A> Ord for Box<T, A>
1.0.0 · source§impl<T, A> PartialOrd for Box<T, A>
impl<T, A> PartialOrd for Box<T, A>
1.0.0 · source§impl<R> Read for Box<R>
impl<R> Read for Box<R>
source§fn read(&mut self, buf: &mut [u8]) -> Result<usize, Error>
fn read(&mut self, buf: &mut [u8]) -> Result<usize, Error>
source§fn read_buf(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>
fn read_buf(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>
read_buf
)source§fn 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 moresource§fn is_read_vectored(&self) -> bool
fn is_read_vectored(&self) -> bool
can_vector
)source§fn 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 moresource§fn 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 moresource§fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Error>
fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Error>
buf
. Read moresource§fn 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 · source§fn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
fn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
Read
. Read more§impl<T> Recorder for Box<T>where
T: Recorder + ?Sized,
impl<T> Recorder for Box<T>where
T: Recorder + ?Sized,
§fn describe_counter(
&self,
key: KeyName,
unit: Option<Unit>,
description: Cow<'static, str>,
)
fn describe_counter( &self, key: KeyName, unit: Option<Unit>, description: Cow<'static, str>, )
§fn describe_gauge(
&self,
key: KeyName,
unit: Option<Unit>,
description: Cow<'static, str>,
)
fn describe_gauge( &self, key: KeyName, unit: Option<Unit>, description: Cow<'static, str>, )
§fn describe_histogram(
&self,
key: KeyName,
unit: Option<Unit>,
description: Cow<'static, str>,
)
fn describe_histogram( &self, key: KeyName, unit: Option<Unit>, description: Cow<'static, str>, )
§fn register_counter(&self, key: &Key, metadata: &Metadata<'_>) -> Counter
fn register_counter(&self, key: &Key, metadata: &Metadata<'_>) -> Counter
§fn register_gauge(&self, key: &Key, metadata: &Metadata<'_>) -> Gauge
fn register_gauge(&self, key: &Key, metadata: &Metadata<'_>) -> Gauge
§fn register_histogram(&self, key: &Key, metadata: &Metadata<'_>) -> Histogram
fn register_histogram(&self, key: &Key, metadata: &Metadata<'_>) -> Histogram
source§impl<R> RngCore for Box<R>
impl<R> RngCore for Box<R>
source§fn fill_bytes(&mut self, dest: &mut [u8])
fn fill_bytes(&mut self, dest: &mut [u8])
dest
with random data. Read more1.0.0 · source§impl<S> Seek for Box<S>
impl<S> Seek for Box<S>
source§fn seek(&mut self, pos: SeekFrom) -> Result<u64, Error>
fn seek(&mut self, pos: SeekFrom) -> Result<u64, Error>
source§fn stream_position(&mut self) -> Result<u64, Error>
fn stream_position(&mut self) -> Result<u64, Error>
1.55.0 · source§fn rewind(&mut self) -> Result<(), Error>
fn rewind(&mut self) -> Result<(), Error>
source§impl<T> Serialize for Box<T>
impl<T> Serialize for Box<T>
source§fn serialize<S>(
&self,
serializer: S,
) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>where
S: Serializer,
fn serialize<S>(
&self,
serializer: S,
) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>where
S: Serializer,
source§impl<T, U> SerializeAs<Box<T>> for Box<U>where
U: SerializeAs<T>,
impl<T, U> SerializeAs<Box<T>> for Box<U>where
U: SerializeAs<T>,
source§fn serialize_as<S>(
source: &Box<T>,
serializer: S,
) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>where
S: Serializer,
fn serialize_as<S>(
source: &Box<T>,
serializer: S,
) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>where
S: Serializer,
§impl<S, Request> Service<Request> for Box<S>where
S: Service<Request> + ?Sized,
impl<S, Request> Service<Request> for Box<S>where
S: Service<Request> + ?Sized,
§impl<S, Item> Sink<Item> for Box<S>
impl<S, Item> Sink<Item> for Box<S>
§fn poll_ready(
self: Pin<&mut Box<S>>,
cx: &mut Context<'_>,
) -> Poll<Result<(), <Box<S> as Sink<Item>>::Error>>
fn poll_ready( self: Pin<&mut Box<S>>, cx: &mut Context<'_>, ) -> Poll<Result<(), <Box<S> as Sink<Item>>::Error>>
Sink
to receive a value. Read more§fn start_send(
self: Pin<&mut Box<S>>,
item: Item,
) -> Result<(), <Box<S> as Sink<Item>>::Error>
fn start_send( self: Pin<&mut Box<S>>, item: Item, ) -> Result<(), <Box<S> as Sink<Item>>::Error>
poll_ready
which returned Poll::Ready(Ok(()))
. Read more§impl<T> Source for Box<T>where
T: Source + ?Sized,
impl<T> Source for Box<T>where
T: Source + ?Sized,
§impl<S> Strategy for Box<S>where
S: Strategy + ?Sized,
impl<S> Strategy for Box<S>where
S: Strategy + ?Sized,
§type Value = <S as Strategy>::Value
type Value = <S as Strategy>::Value
§fn new_tree(
&self,
runner: &mut TestRunner,
) -> Result<<Box<S> as Strategy>::Tree, Reason>
fn new_tree( &self, runner: &mut TestRunner, ) -> Result<<Box<S> as Strategy>::Tree, Reason>
§fn prop_map<O, F>(self, fun: F) -> Map<Self, F>
fn prop_map<O, F>(self, fun: F) -> Map<Self, F>
fun
. Read more§fn prop_map_into<O>(self) -> MapInto<Self, O>
fn prop_map_into<O>(self) -> MapInto<Self, O>
§fn prop_perturb<O, F>(self, fun: F) -> Perturb<Self, F>
fn prop_perturb<O, F>(self, fun: F) -> Perturb<Self, F>
fun
, which is additionally given a random number generator. Read more§fn prop_flat_map<S, F>(self, fun: F) -> Flatten<Map<Self, F>>
fn prop_flat_map<S, F>(self, fun: F) -> Flatten<Map<Self, F>>
§fn prop_ind_flat_map<S, F>(self, fun: F) -> IndFlatten<Map<Self, F>>
fn prop_ind_flat_map<S, F>(self, fun: F) -> IndFlatten<Map<Self, F>>
§fn prop_ind_flat_map2<S, F>(self, fun: F) -> IndFlattenMap<Self, F>
fn prop_ind_flat_map2<S, F>(self, fun: F) -> IndFlattenMap<Self, F>
prop_ind_flat_map()
, but produces 2-tuples with the input
generated from self
in slot 0 and the derived strategy in slot 1. Read more§fn prop_filter<R, F>(self, whence: R, fun: F) -> Filter<Self, F>
fn prop_filter<R, F>(self, whence: R, fun: F) -> Filter<Self, F>
fun
. Read more§fn prop_filter_map<F, O>(
self,
whence: impl Into<Reason>,
fun: F,
) -> FilterMap<Self, F>
fn prop_filter_map<F, O>( self, whence: impl Into<Reason>, fun: F, ) -> FilterMap<Self, F>
fun
returns Some(value)
and rejects those where fun
returns None
. Read more§fn prop_union(self, other: Self) -> Union<Self>where
Self: Sized,
fn prop_union(self, other: Self) -> Union<Self>where
Self: Sized,
§fn prop_recursive<R, F>(
self,
depth: u32,
desired_size: u32,
expected_branch_size: u32,
recurse: F,
) -> Recursive<Self::Value, F>
fn prop_recursive<R, F>( self, depth: u32, desired_size: u32, expected_branch_size: u32, recurse: F, ) -> Recursive<Self::Value, F>
self
items as leaves. Read more§impl<S> Stream for Box<S>
impl<S> Stream for Box<S>
§impl<S> Subscriber for Box<S>where
S: Subscriber + ?Sized,
impl<S> Subscriber for Box<S>where
S: Subscriber + ?Sized,
§fn register_callsite(&self, metadata: &'static Metadata<'static>) -> Interest
fn register_callsite(&self, metadata: &'static Metadata<'static>) -> Interest
§fn max_level_hint(&self) -> Option<LevelFilter>
fn max_level_hint(&self) -> Option<LevelFilter>
Subscriber
will
enable, or None
, if the subscriber does not implement level-based
filtering or chooses not to implement this method. Read more§fn record_follows_from(&self, span: &Id, follows: &Id)
fn record_follows_from(&self, span: &Id, follows: &Id)
§fn event_enabled(&self, event: &Event<'_>) -> bool
fn event_enabled(&self, event: &Event<'_>) -> bool
Event
] should be recorded. Read more§fn clone_span(&self, id: &Id) -> Id
fn clone_span(&self, id: &Id) -> Id
§fn drop_span(&self, id: Id)
fn drop_span(&self, id: Id)
Subscriber::try_close
instead§fn current_span(&self) -> Current
fn current_span(&self) -> Current
§unsafe fn downcast_raw(&self, id: TypeId) -> Option<*const ()>
unsafe fn downcast_raw(&self, id: TypeId) -> Option<*const ()>
self
is the same type as the provided TypeId
, returns an untyped
*const
pointer to that type. Otherwise, returns None
. Read more§fn on_register_dispatch(&self, subscriber: &Dispatch)
fn on_register_dispatch(&self, subscriber: &Dispatch)
Dispatch
]. Read more§impl<T> ValueTree for Box<T>where
T: ValueTree + ?Sized,
impl<T> ValueTree for Box<T>where
T: ValueTree + ?Sized,
§fn simplify(&mut self) -> bool
fn simplify(&mut self) -> bool
§fn complicate(&mut self) -> bool
fn complicate(&mut self) -> bool
§impl<T> Write for Box<T>
impl<T> Write for Box<T>
§fn poll_write(
self: Pin<&mut Box<T>>,
cx: &mut Context<'_>,
buf: &[u8],
) -> Poll<Result<usize, Error>>
fn poll_write( self: Pin<&mut Box<T>>, cx: &mut Context<'_>, buf: &[u8], ) -> Poll<Result<usize, Error>>
buf
into the destination. Read more§fn poll_write_vectored(
self: Pin<&mut Box<T>>,
cx: &mut Context<'_>,
bufs: &[IoSlice<'_>],
) -> Poll<Result<usize, Error>>
fn poll_write_vectored( self: Pin<&mut Box<T>>, cx: &mut Context<'_>, bufs: &[IoSlice<'_>], ) -> Poll<Result<usize, Error>>
poll_write
, except that it writes from a slice of buffers.§fn is_write_vectored(&self) -> bool
fn is_write_vectored(&self) -> bool
poll_write_vectored
implementation. Read more1.0.0 · source§impl<W> Write for Box<W>
impl<W> Write for Box<W>
source§fn write(&mut self, buf: &[u8]) -> Result<usize, Error>
fn write(&mut self, buf: &[u8]) -> Result<usize, Error>
source§fn is_write_vectored(&self) -> bool
fn is_write_vectored(&self) -> bool
can_vector
)