Struct Writer 

pub struct Writer<'buf> { /* private fields */ }

A type implementing io::Write for a potentially uninitialized slice of memory.

The explicit intent is to enable formatted writing to uninitialized stack allocated memory, which is “allocatable” with a mere increment of the stack pointer. E.g.,

let mut buffer = [MaybeUninit::<u8>::uninit(); 256];
let mut writer = bufio::Writer::new(&mut buffer);
write!(writer, "{:x}", 1337).unwrap();
// Of course if you are writing to stdout you might as well use
// `print!` or `write!`; this example is just for illustration
// purposes.
stdout().write(writer.written()).unwrap();

Implementations

impl<'buf> Writer<'buf>

pub fn new(buffer: &'buf mut [MaybeUninit<u8>]) -> Self

Create a new Writer using the provided slice as buffer memory to write to.

pub fn written(&self) -> &'buf [u8]

Retrieve the number of bytes written to the underlying buffer.

pub fn reset(&mut self)

Reset the buffer to its “empty” state.

Trait Implementations

impl<'buf> Debug for Writer<'buf>

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

Formats the value using the given formatter.

impl Write for Writer<'_>

fn write(&mut self, data: &[u8]) -> Result<usize>

Writes a buffer into this writer, returning how many bytes were written.

fn flush(&mut self) -> Result<()>

Flushes this output stream, ensuring that all intermediately buffered contents reach their destination.

fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> Result<usize, Error>

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

fn is_write_vectored(&self) -> bool

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

Determines if this Writer has an efficient write_vectored implementation.

fn write_all(&mut self, buf: &[u8]) -> Result<(), Error>

Attempts to write an entire buffer into this writer.

fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error>

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

Attempts to write multiple buffers into this writer.

fn write_fmt(&mut self, args: Arguments<'_>) -> Result<(), Error>

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

fn by_ref(&mut self) -> &mut Self

where Self: Sized,

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