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pub struct Global;
🔬 This is a nightly-only experimental API. (allocator_api)
Available on crate feature mtls only.
Expand description

The global memory allocator.

This type implements the Allocator trait by forwarding calls to the allocator registered with the #[global_allocator] attribute if there is one, or the std crate’s default.

Note: while this type is unstable, the functionality it provides can be accessed through the free functions in alloc.

Implementations

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);
🔬 This is a nightly-only experimental API. (new_uninit)

Constructs a new box with uninitialized contents.

Examples
#![feature(new_uninit)]

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)
🔬 This is a nightly-only experimental API. (new_uninit)

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_uninit)]

let zero = Box::<u32>::new_zeroed();
let zero = unsafe { zero.assume_init() };

assert_eq!(*zero, 0)

Constructs a new Pin<Box<T>>. If T does not implement Unpin, then x will be pinned in memory and unable to be moved.

🔬 This is a nightly-only experimental API. (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)?;
🔬 This is a nightly-only experimental API. (allocator_api)

Constructs a new box with uninitialized contents on the heap, returning an error if the allocation fails

Examples
#![feature(allocator_api, new_uninit)]

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);
🔬 This is a nightly-only experimental API. (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, new_uninit)]

let zero = Box::<u32>::try_new_zeroed()?;
let zero = unsafe { zero.assume_init() };

assert_eq!(*zero, 0);
🔬 This is a nightly-only experimental API. (new_uninit)

Constructs a new boxed slice with uninitialized contents.

Examples
#![feature(new_uninit)]

let mut values = Box::<[u32]>::new_uninit_slice(3);

let values = unsafe {
    // Deferred initialization:
    values[0].as_mut_ptr().write(1);
    values[1].as_mut_ptr().write(2);
    values[2].as_mut_ptr().write(3);

    values.assume_init()
};

assert_eq!(*values, [1, 2, 3])
🔬 This is a nightly-only experimental API. (new_uninit)

Constructs a new boxed slice 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_uninit)]

let values = Box::<[u32]>::new_zeroed_slice(3);
let values = unsafe { values.assume_init() };

assert_eq!(*values, [0, 0, 0])
🔬 This is a nightly-only experimental API. (allocator_api)

Constructs a new boxed slice with uninitialized contents. Returns an error if the allocation fails

Examples
#![feature(allocator_api, new_uninit)]

let mut values = Box::<[u32]>::try_new_uninit_slice(3)?;
let values = unsafe {
    // Deferred initialization:
    values[0].as_mut_ptr().write(1);
    values[1].as_mut_ptr().write(2);
    values[2].as_mut_ptr().write(3);
    values.assume_init()
};

assert_eq!(*values, [1, 2, 3]);
🔬 This is a nightly-only experimental API. (allocator_api)

Constructs a new boxed slice with uninitialized contents, with the memory being filled with 0 bytes. Returns an error if the allocation fails

See MaybeUninit::zeroed for examples of correct and incorrect usage of this method.

Examples
#![feature(allocator_api, new_uninit)]

let values = Box::<[u32]>::try_new_zeroed_slice(3)?;
let values = unsafe { values.assume_init() };

assert_eq!(*values, [0, 0, 0]);

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);
}

Trait Implementations

🔬 This is a nightly-only experimental API. (allocator_api)

Attempts to allocate a block of memory. Read more

🔬 This is a nightly-only experimental API. (allocator_api)

Behaves like allocate, but also ensures that the returned memory is zero-initialized. Read more

🔬 This is a nightly-only experimental API. (allocator_api)

Deallocates the memory referenced by ptr. Read more

🔬 This is a nightly-only experimental API. (allocator_api)

Attempts to extend the memory block. Read more

🔬 This is a nightly-only experimental API. (allocator_api)

Behaves like grow, but also ensures that the new contents are set to zero before being returned. Read more

🔬 This is a nightly-only experimental API. (allocator_api)

Attempts to shrink the memory block. Read more

🔬 This is a nightly-only experimental API. (allocator_api)

Creates a “by reference” adapter for this instance of Allocator. Read more

Attempt to return the contents of the internal buffer, filling it with more data from the inner reader if it is empty. Read more

Tells this buffer that amt bytes have been consumed from the buffer, so they should no longer be returned in calls to poll_read. Read more

Attempts to return the contents of the internal buffer, filling it with more data from the inner reader if it is empty. Read more

Tells this buffer that amt bytes have been consumed from the buffer, so they should no longer be returned in calls to poll_read. Read more

🔬 This is a nightly-only experimental API. (async_iterator)

The type of items yielded by the async iterator.

🔬 This is a nightly-only experimental API. (async_iterator)

Attempt to pull out the next value of this async iterator, registering the current task for wakeup if the value is not yet available, and returning None if the async iterator is exhausted. Read more

🔬 This is a nightly-only experimental API. (async_iterator)

Returns the bounds on the remaining length of the async iterator. Read more

Attempt to read from the AsyncRead into buf. Read more

Attempt to read from the AsyncRead into bufs using vectored IO operations. Read more

Attempts to read from the AsyncRead into buf. Read more

Attempt to seek to an offset, in bytes, in a stream. Read more

Attempts to seek to an offset, in bytes, in a stream. Read more

Waits for a seek operation to complete. Read more

Attempt to write bytes from buf into the object. Read more

Attempt to write bytes from bufs into the object using vectored IO operations. Read more

Attempt to flush the object, ensuring that any buffered data reach their destination. Read more

Attempt to close the object. Read more

Attempt to write bytes from buf into the object. Read more

Like poll_write, except that it writes from a slice of buffers. Read more

Determines if this writer has an efficient poll_write_vectored implementation. Read more

Attempts to flush the object, ensuring that any buffered data reach their destination. Read more

Initiates or attempts to shut down this writer, returning success when the I/O connection has completely shut down. Read more

Values yielded by the Body.

The error type this Body might generate.

Attempt to pull out the next data buffer of this stream.

Poll for an optional single HeaderMap of trailers. Read more

Returns true when the end of stream has been reached. Read more

Returns the bounds on the remaining length of the stream. Read more

Returns future that resolves to next data chunk, if any.

Returns future that resolves to trailers, if any.

Maps this body’s data value to a different value.

Maps this body’s error value to a different value.

Turn this body into a boxed trait object.

Turn this body into a boxed trait object that is !Sync.

Returns the number of bytes between the current position and the end of the buffer. Read more

Returns a slice starting at the current position and of length between 0 and Buf::remaining(). Note that this can return shorter slice (this allows non-continuous internal representation). Read more

Fills dst with potentially multiple slices starting at self’s current position. Read more

Advance the internal cursor of the Buf Read more

Returns true if there are any more bytes to consume Read more

Copies bytes from self into dst. Read more

Gets an unsigned 8 bit integer from self. Read more

Gets a signed 8 bit integer from self. Read more

Gets an unsigned 16 bit integer from self in big-endian byte order. Read more

Gets an unsigned 16 bit integer from self in little-endian byte order. Read more

Gets a signed 16 bit integer from self in big-endian byte order. Read more

Gets a signed 16 bit integer from self in little-endian byte order. Read more

Gets an unsigned 32 bit integer from self in the big-endian byte order. Read more

Gets an unsigned 32 bit integer from self in the little-endian byte order. Read more

Gets a signed 32 bit integer from self in big-endian byte order. Read more

Gets a signed 32 bit integer from self in little-endian byte order. Read more

Gets an unsigned 64 bit integer from self in big-endian byte order. Read more

Gets an unsigned 64 bit integer from self in little-endian byte order. Read more

Gets a signed 64 bit integer from self in big-endian byte order. Read more

Gets a signed 64 bit integer from self in little-endian byte order. Read more

Gets an unsigned n-byte integer from self in big-endian byte order. Read more

Gets an unsigned n-byte integer from self in little-endian byte order. Read more

Gets a signed n-byte integer from self in big-endian byte order. Read more

Gets a signed n-byte integer from self in little-endian byte order. Read more

Consumes len bytes inside self and returns new instance of Bytes with this data. Read more

Gets an unsigned 128 bit integer from self in big-endian byte order. Read more

Gets an unsigned 128 bit integer from self in little-endian byte order. Read more

Gets a signed 128 bit integer from self in big-endian byte order. Read more

Gets a signed 128 bit integer from self in little-endian byte order. Read more

Gets an IEEE754 single-precision (4 bytes) floating point number from self in big-endian byte order. Read more

Gets an IEEE754 single-precision (4 bytes) floating point number from self in little-endian byte order. Read more

Gets an IEEE754 double-precision (8 bytes) floating point number from self in big-endian byte order. Read more

Gets an IEEE754 double-precision (8 bytes) floating point number from self in little-endian byte order. Read more

Creates an adaptor which will read at most limit bytes from self. Read more

Creates an adaptor which will chain this buffer with another. Read more

Creates an adaptor which implements the Read trait for self. Read more

Returns the number of bytes that can be written from the current position until the end of the buffer is reached. Read more

Returns a mutable slice starting at the current BufMut position and of length between 0 and BufMut::remaining_mut(). Note that this can be shorter than the whole remainder of the buffer (this allows non-continuous implementation). Read more

Advance the internal cursor of the BufMut Read more

Transfer bytes into self from src and advance the cursor by the number of bytes written. Read more

Writes an unsigned 8 bit integer to self. Read more

Writes a signed 8 bit integer to self. Read more

Writes an unsigned 16 bit integer to self in big-endian byte order. Read more

Writes an unsigned 16 bit integer to self in little-endian byte order. Read more

Writes a signed 16 bit integer to self in big-endian byte order. Read more

Writes a signed 16 bit integer to self in little-endian byte order. Read more

Writes an unsigned 32 bit integer to self in big-endian byte order. Read more

Writes an unsigned 32 bit integer to self in little-endian byte order. Read more

Writes a signed 32 bit integer to self in big-endian byte order. Read more

Writes a signed 32 bit integer to self in little-endian byte order. Read more

Writes an unsigned 64 bit integer to self in the big-endian byte order. Read more

Writes an unsigned 64 bit integer to self in little-endian byte order. Read more

Writes a signed 64 bit integer to self in the big-endian byte order. Read more

Writes a signed 64 bit integer to self in little-endian byte order. Read more

Returns true if there is space in self for more bytes. Read more

Transfer bytes into self from src and advance the cursor by the number of bytes written. Read more

Put cnt bytes val into self. Read more

Writes an unsigned 128 bit integer to self in the big-endian byte order. Read more

Writes an unsigned 128 bit integer to self in little-endian byte order. Read more

Writes a signed 128 bit integer to self in the big-endian byte order. Read more

Writes a signed 128 bit integer to self in little-endian byte order. Read more

Writes an unsigned n-byte integer to self in big-endian byte order. Read more

Writes an unsigned n-byte integer to self in the little-endian byte order. Read more

Writes low nbytes of a signed integer to self in big-endian byte order. Read more

Writes low nbytes of a signed integer to self in little-endian byte order. Read more

Writes an IEEE754 single-precision (4 bytes) floating point number to self in big-endian byte order. Read more

Writes an IEEE754 single-precision (4 bytes) floating point number to self in little-endian byte order. Read more

Writes an IEEE754 double-precision (8 bytes) floating point number to self in big-endian byte order. Read more

Writes an IEEE754 double-precision (8 bytes) floating point number to self in little-endian byte order. Read more

Creates an adaptor which can write at most limit bytes to self. Read more

Creates an adaptor which implements the Write trait for self. Read more

Creates an adapter which will chain this buffer with another. Read more

Returns the contents of the internal buffer, filling it with more data from the inner reader if it is empty. Read more

Tells this buffer that amt bytes have been consumed from the buffer, so they should no longer be returned in calls to read. Read more

Read all bytes into buf until the delimiter byte or EOF is reached. Read more

Read all bytes until a newline (the 0xA byte) is reached, and append them to the provided buffer. You do not need to clear the buffer before appending. Read more

🔬 This is a nightly-only experimental API. (buf_read_has_data_left)

Check if the underlying Read has any data left to be read. Read more

Returns an iterator over the contents of this reader split on the byte byte. Read more

Returns an iterator over the lines of this reader. Read more

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Formats the value using the given formatter. Read more

Formats the value using the given formatter. Read more

Formats the value using the given formatter. Read more

Returns the “default value” for a type. Read more

Returns the “default value” for a type. Read more

Returns the “default value” for a type. Read more

Returns the “default value” for a type. Read more

Creates a Box<T>, with the Default value for T.

Returns the “default value” for a type. Read more

Returns the “default value” for a type. Read more

Deserialize this value from the given Serde deserializer. Read more

Deserialize this value from the given Serde deserializer. Read more

Deserialize this value from the given Serde deserializer. Read more

Deserialize this value from the given Serde deserializer. Read more

Deserialize this value from the given Serde deserializer. Read more

Deserialize this value from the given Serde deserializer. Read more

👎 Deprecated since 1.42.0:

use the Display impl or to_string()

👎 Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

The lower-level source of this error, if any. Read more

🔬 This is a nightly-only experimental API. (backtrace)

Returns a stack backtrace, if available, of where this error occurred. Read more

Converts a &[T] into a Box<[T]>

This conversion allocates on the heap and performs a copy of slice.

Examples
// create a &[u8] which will be used to create a Box<[u8]>
let slice: &[u8] = &[104, 101, 108, 108, 111];
let boxed_slice: Box<[u8]> = Box::from(slice);

println!("{boxed_slice:?}");

Converts a &CStr into a Box<CStr>, by copying the contents into a newly allocated Box.

Copies the string into a newly allocated Box<OsStr>.

Creates a boxed Path from a reference.

This will allocate and clone path to it.

Converts a str into a box of dyn Error + Send + Sync.

Examples
use std::error::Error;
use std::mem;

let a_str_error = "a str error";
let a_boxed_error = Box::<dyn Error + Send + Sync>::from(a_str_error);
assert!(
    mem::size_of::<Box<dyn Error + Send + Sync>>() == mem::size_of_val(&a_boxed_error))

Converts a str into a box of dyn Error.

Examples
use std::error::Error;
use std::mem;

let a_str_error = "a str error";
let a_boxed_error = Box::<dyn Error>::from(a_str_error);
assert!(mem::size_of::<Box<dyn Error>>() == mem::size_of_val(&a_boxed_error))

Converts a &str into a Box<str>

This conversion allocates on the heap and performs a copy of s.

Examples
let boxed: Box<str> = Box::from("hello");
println!("{boxed}");

Converts a [T; N] into a Box<[T]>

This conversion moves the array to newly heap-allocated memory.

Examples
let boxed: Box<[u8]> = Box::from([4, 2]);
println!("{boxed:?}");

Converts to this type from the input type.

Converts a CString into a Box<CStr> without copying or allocating.

Converts a Cow<'_, [T]> into a Box<[T]>

When cow is the Cow::Borrowed variant, this conversion allocates on the heap and copies the underlying slice. Otherwise, it will try to reuse the owned Vec’s allocation.

Converts a Cow<'a, CStr> into a Box<CStr>, by copying the contents if they are borrowed.

Converts a Cow<'a, OsStr> into a Box<OsStr>, by copying the contents if they are borrowed.

Creates a boxed Path from a clone-on-write pointer.

Converting from a Cow::Owned does not clone or allocate.

Converts a Cow<'_, str> into a Box<str>

When cow is the Cow::Borrowed variant, this conversion allocates on the heap and copies the underlying str. Otherwise, it will try to reuse the owned String’s allocation.

Examples
use std::borrow::Cow;

let unboxed = Cow::Borrowed("hello");
let boxed: Box<str> = Box::from(unboxed);
println!("{boxed}");
let unboxed = Cow::Owned("hello".to_string());
let boxed: Box<str> = Box::from(unboxed);
println!("{boxed}");

Converts a Cow into a box of dyn Error.

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>::from(a_cow_str_error);
assert!(mem::size_of::<Box<dyn Error>>() == mem::size_of_val(&a_boxed_error))

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))

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))

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))

Converts an OsString into a Box<OsStr> without copying or allocating.

Converts a PathBuf into a Box<Path>.

This conversion currently should not allocate memory, but this behavior is not guaranteed on all platforms or in all future versions.

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))

Converts a String into a box of dyn Error.

Examples
use std::error::Error;
use std::mem;

let a_string_error = "a string error".to_string();
let a_boxed_error = Box::<dyn Error>::from(a_string_error);
assert!(mem::size_of::<Box<dyn Error>>() == mem::size_of_val(&a_boxed_error))

Converts the given String to a boxed str slice that is owned.

Examples

Basic usage:

let s1: String = String::from("hello world");
let s2: Box<str> = Box::from(s1);
let s3: String = String::from(s2);

assert_eq!("hello world", s3)

Converts a T into a Box<T>

The conversion allocates on the heap and moves t from the stack into it.

Examples
let x = 5;
let boxed = Box::new(5);

assert_eq!(Box::from(x), boxed);

Creates a value from an iterator. Read more

Returns true if the underlying future should no longer be polled.

Returns true if the stream should no longer be polled.

Spawns a future that will be run to completion. Read more

Determines whether the executor is able to spawn new tasks. Read more

Determines if a log message with the specified metadata would be logged. Read more

Logs the Record. Read more

Flushes any buffered records.

A parser takes in input type, and returns a Result containing either the remaining input and the output value, or an error Read more

Maps a function over the result of a parser

Creates a second parser from the output of the first one, then apply over the rest of the input

Applies a second parser over the output of the first one

Applies a second parser after the first one, return their results as a tuple

Applies a second parser over the input if the first one failed

automatically converts the parser’s output and error values to another type, as long as they implement the From trait Read more

Pull some bytes from this source into the specified buffer, returning how many bytes were read. Read more

🔬 This is a nightly-only experimental API. (read_buf)

Pull some bytes from this source into the specified buffer. Read more

Like read, except that it reads into a slice of buffers. Read more

🔬 This is a nightly-only experimental API. (can_vector)

Determines if this Reader has an efficient read_vectored implementation. Read more

Read all bytes until EOF in this source, placing them into buf. Read more

Read all bytes until EOF in this source, appending them to buf. Read more

Read the exact number of bytes required to fill buf. Read more

🔬 This is a nightly-only experimental API. (read_buf)

Read the exact number of bytes required to fill buf. Read more

Creates a “by reference” adaptor for this instance of Read. Read more

Transforms this Read instance to an Iterator over its bytes. Read more

Creates an adapter which will chain this stream with another. Read more

Creates an adapter which will read at most limit bytes from it. Read more

Return the next random u32. Read more

Return the next random u64. Read more

Fill dest with random data. Read more

Fill dest entirely with random data. Read more

Seek to an offset, in bytes, in a stream. Read more

Returns the current seek position from the start of the stream. Read more

Rewind to the beginning of a stream. Read more

🔬 This is a nightly-only experimental API. (seek_stream_len)

Returns the length of this stream (in bytes). Read more

Serialize this value into the given Serde serializer. Read more

Responses given by the service.

Errors produced by the service.

The future response value.

Returns Poll::Ready(Ok(())) when the service is able to process requests. Read more

Process the request and return the response asynchronously. Read more

The type of value produced by the sink when an error occurs.

Attempts to prepare the Sink to receive a value. Read more

Begin the process of sending a value to the sink. Each call to this function must be preceded by a successful call to poll_ready which returned Poll::Ready(Ok(())). Read more

Flush any remaining output from this sink. Read more

Flush any remaining output and close this sink, if necessary. Read more

Register self with the given Registry instance. Read more

Re-register self with the given Registry instance. Read more

Deregister self from the given Registry instance. Read more

Spawns a future that will be run to completion. Read more

Determines whether the executor is able to spawn new tasks. Read more

Values yielded by the stream.

Attempt to pull out the next value of this stream, registering the current task for wakeup if the value is not yet available, and returning None if the stream is exhausted. Read more

Returns the bounds on the remaining length of the stream. Read more

Registers a new callsite with this subscriber, returning whether or not the subscriber is interested in being notified about the callsite. Read more

Returns true if a span or event with the specified metadata would be recorded. Read more

Returns the highest verbosity level that this Subscriber will enable, or None, if the subscriber does not implement level-based filtering or chooses not to implement this method. Read more

Visit the construction of a new span, returning a new span ID for the span being constructed. Read more

Record a set of values on a span. Read more

Adds an indication that span follows from the span with the id follows. Read more

Records that an Event has occurred. Read more

Records that a span has been entered. Read more

Records that a span has been exited. Read more

Notifies the subscriber that a span ID has been cloned. Read more

Notifies the subscriber that a span ID has been dropped, and returns true if there are now 0 IDs that refer to that span. Read more

👎 Deprecated since 0.1.2:

use Subscriber::try_close instead

This method is deprecated. Read more

Returns a type representing this subscriber’s view of the current span. Read more

If self is the same type as the provided TypeId, returns an untyped *const pointer to that type. Otherwise, returns None. Read more

Attempts to convert a Box<[T]> into a Box<[T; N]>.

The conversion occurs in-place and does not require a new memory allocation.

Errors

Returns the old Box<[T]> in the Err variant if boxed_slice.len() does not equal N.

The type returned in the event of a conversion error.

Convert an owned instance into a (conceptually owned) fat pointer. Read more

Drops the future represented by the given fat pointer. Read more

Convert an owned instance into a (conceptually owned) fat pointer. Read more

Drops the future represented by the given fat pointer. Read more

Convert an owned instance into a (conceptually owned) fat pointer. Read more

Drops the future represented by the given fat pointer. Read more

Visits this value with the given Visitor.

Write a buffer into this writer, returning how many bytes were written. Read more

Like write, except that it writes from a slice of buffers. Read more

🔬 This is a nightly-only experimental API. (can_vector)

Determines if this Writer has an efficient write_vectored implementation. Read more

Flush this output stream, ensuring that all intermediately buffered contents reach their destination. Read more

Attempts to write an entire buffer into this writer. Read more

Writes a formatted string into this writer, returning any error encountered. Read more

🔬 This is a nightly-only experimental API. (write_all_vectored)

Attempts to write multiple buffers into this writer. Read more

Creates a “by reference” adapter for this instance of Write. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Instruments this type with the provided Span, returning an Instrumented wrapper. Read more

Instruments this type with the current Span, returning an Instrumented wrapper. Read more

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

Converts self into a collection.

Should always be Self

The resulting type after obtaining ownership.

Creates owned data from borrowed data, usually by cloning. Read more

🔬 This is a nightly-only experimental API. (toowned_clone_into)

Uses borrowed data to replace owned data, usually by cloning. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.

Attaches the provided Subscriber to this type, returning a WithDispatch wrapper. Read more

Attaches the current default Subscriber to this type, returning a WithDispatch wrapper. Read more