Struct NumberWriter

pub struct NumberWriter<W: Write> { /* private fields */ }

A NumberWriter wraps a writer and provides methods for writing numbers.

Unlike many libraries, which take byte order as a parameter per operation, a NumberWriter takes byte order as a parameter upon initialization.

Examples

We can create a new NumberWriter using the target endianness using NumberWriter::new:

use byte_order::NumberWriter;

let mut writer = NumberWriter::new(vec![]);

Or, to write numbers with a certain endianness, we can create NumberWriter structures using NumberWriter::with_order:

use byte_order::{ByteOrder, NumberWriter};

let mut be_writer = NumberWriter::with_order(ByteOrder::BE, vec![]);
let mut le_writer = NumberWriter::with_order(ByteOrder::LE, vec![]);
let mut ne_writer = NumberWriter::with_order(ByteOrder::NE, vec![]);

To write numbers from the underlying writer, use any of the write_* methods that are provided:

use std::io;
use byte_order::{ByteOrder, NumberWriter};

fn main() -> io::Result<()> {
    let mut be_writer = NumberWriter::with_order(ByteOrder::BE, vec![]);
    be_writer.write_u16(0xA1B2)?;
    assert_eq!(be_writer.into_inner(), vec![0xA1, 0xB2]);

    let mut le_writer = NumberWriter::with_order(ByteOrder::LE, vec![]);
    le_writer.write_u16(0xA1B2)?;
    assert_eq!(le_writer.into_inner(), vec![0xB2, 0xA1]);

    let mut ne_writer = NumberWriter::with_order(ByteOrder::NE, vec![]);
    ne_writer.write_u16(0xA1B2)?;
    assert_eq!(
        ne_writer.into_inner(),
        if cfg!(target_endian = "big") {
            vec![0xA1, 0xB2]
        } else {
            vec![0xB2, 0xA1]
        }
    );

    Ok(())
}

Implementations

impl<W: Write> NumberWriter<W>

pub fn new(w: W) -> NumberWriter<W>

pub fn with_order(order: ByteOrder, w: W) -> NumberWriter<W>

pub fn into_inner(self) -> W

Consumes this NumberReader, returning the underlying value.

Examples

use std::io::Cursor;
use byte_order::NumberReader;

let reader = NumberReader::new(Cursor::new(vec![]));

let cursor = reader.into_inner();

pub fn get_ref(&self) -> &W

Gets a reference to the underlying value in this NumberReader.

Examples

use std::io::Cursor;
use byte_order::NumberReader;

let reader = NumberReader::new(Cursor::new(vec![]));

let reference = reader.get_ref();

pub fn get_mut(&mut self) -> &mut W

Gets a mutable reference to the underlying value in this NumberReader.

Examples

use std::io::Cursor;
use byte_order::NumberReader;

let mut reader = NumberReader::new(Cursor::new(vec![]));

let reference = reader.get_mut();

pub fn write_u8(&mut self, n: u8) -> Result<()>

Writes an unsigned 8-bit integer to the underlying writer.

Note: Since this method reads a single byte, no byte order conversions are used. It is included for completeness.

Errors

This method propagates any error recieved from the internal call to Write::write_all.

Examples

use std::io;
use byte_order::NumberWriter;

fn main() -> io::Result<()> {
    let mut writer = NumberWriter::new(vec![]);
    writer.write_u8(0x12u8)?;
    assert_eq!(writer.into_inner(), vec![0x12]);
    Ok(())
}

pub fn write_i8(&mut self, n: i8) -> Result<()>

Writes an signed 8-bit integer to the underlying writer.

Note: Since this method reads a single byte, no byte order conversions are used. It is included for completeness.

Errors

This method propagates any error recieved from the internal call to Write::write_all.

Examples

use std::io;
use byte_order::NumberWriter;

fn main() -> io::Result<()> {
    let mut writer = NumberWriter::new(vec![]);
    writer.write_u8(0x12u8)?;
    assert_eq!(writer.into_inner(), vec![0x12]);
    Ok(())
}

pub fn write_u16(&mut self, n: u16) -> Result<()>

Writes an unsigned 16-bit integer to the underlying writer.

Errors

This method propagates any error recieved from the internal call to Write::write_all.

Examples

use std::io;
use byte_order::{ByteOrder, NumberWriter};

fn main() -> io::Result<()> {
    let n = 0x1234u16;

    let mut be_writer = NumberWriter::with_order(ByteOrder::BE, vec![]);
    be_writer.write_u16(n)?;
    assert_eq!(be_writer.into_inner(), vec![0x12, 0x34]);

    let mut le_writer = NumberWriter::with_order(ByteOrder::LE, vec![]);
    le_writer.write_u16(n)?;
    assert_eq!(le_writer.into_inner(), vec![0x34, 0x12]);

    Ok(())
}

pub fn write_i16(&mut self, n: i16) -> Result<()>

Writes a signed 16-bit integer to the underlying writer.

Errors

This method propagates any error recieved from the internal call to Write::write_all.

Examples

use std::io;
use byte_order::{ByteOrder, NumberWriter};

fn main() -> io::Result<()> {
    let n = 0x1234i16;

    let mut be_writer = NumberWriter::with_order(ByteOrder::BE, vec![]);
    be_writer.write_i16(n)?;
    assert_eq!(be_writer.into_inner(), vec![0x12, 0x34]);

    let mut le_writer = NumberWriter::with_order(ByteOrder::LE, vec![]);
    le_writer.write_i16(n)?;
    assert_eq!(le_writer.into_inner(), vec![0x34, 0x12]);

    Ok(())
}

pub fn write_u32(&mut self, n: u32) -> Result<()>

Writes an unsigned 32-bit integer to the underlying writer.

Errors

This method propagates any error recieved from the internal call to Write::write_all.

Examples

use std::io;
use byte_order::{ByteOrder, NumberWriter};

fn main() -> io::Result<()> {
    let n = 0x12345678u32;

    let mut be_writer = NumberWriter::with_order(ByteOrder::BE, vec![]);
    be_writer.write_u32(n)?;
    assert_eq!(be_writer.into_inner(), vec![0x12, 0x34, 0x56, 0x78]);

    let mut le_writer = NumberWriter::with_order(ByteOrder::LE, vec![]);
    le_writer.write_u32(n)?;
    assert_eq!(le_writer.into_inner(), vec![0x78, 0x56, 0x34, 0x12]);

    Ok(())
}

pub fn write_i32(&mut self, n: i32) -> Result<()>

Writes a signed 32-bit integer to the underlying writer.

Errors

This method propagates any error recieved from the internal call to Write::write_all.

Examples

use std::io;
use byte_order::{ByteOrder, NumberWriter};

fn main() -> io::Result<()> {
    let n = 0x12345678i32;

    let mut be_writer = NumberWriter::with_order(ByteOrder::BE, vec![]);
    be_writer.write_i32(n)?;
    assert_eq!(be_writer.into_inner(), vec![0x12, 0x34, 0x56, 0x78]);

    let mut le_writer = NumberWriter::with_order(ByteOrder::LE, vec![]);
    le_writer.write_i32(n)?;
    assert_eq!(le_writer.into_inner(), vec![0x78, 0x56, 0x34, 0x12]);

    Ok(())
}

pub fn write_u64(&mut self, n: u64) -> Result<()>

Writes an unsigned 64-bit integer to the underlying writer.

Errors

This method propagates any error recieved from the internal call to Write::write_all.

Examples

use std::io;
use byte_order::{ByteOrder, NumberWriter};

fn main() -> io::Result<()> {
    let n = 0x1234567890123456u64;

    let mut be_writer = NumberWriter::with_order(ByteOrder::BE, vec![]);
    be_writer.write_u64(n)?;
    assert_eq!(be_writer.into_inner(), vec![0x12, 0x34, 0x56, 0x78, 0x90, 0x12, 0x34, 0x56]);

    let mut le_writer = NumberWriter::with_order(ByteOrder::LE, vec![]);
    le_writer.write_u64(n)?;
    assert_eq!(le_writer.into_inner(), vec![0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12]);

    Ok(())
}

pub fn write_i64(&mut self, n: i64) -> Result<()>

Writes a signed 64-bit integer to the underlying writer.

Errors

This method propagates any error recieved from the internal call to Write::write_all.

Examples

use std::io;
use byte_order::{ByteOrder, NumberWriter};

fn main() -> io::Result<()> {
    let n = 0x1234567890123456i64;

    let mut be_writer = NumberWriter::with_order(ByteOrder::BE, vec![]);
    be_writer.write_i64(n)?;
    assert_eq!(be_writer.into_inner(), vec![0x12, 0x34, 0x56, 0x78, 0x90, 0x12, 0x34, 0x56]);

    let mut le_writer = NumberWriter::with_order(ByteOrder::LE, vec![]);
    le_writer.write_i64(n)?;
    assert_eq!(le_writer.into_inner(), vec![0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12]);

    Ok(())
}

pub fn write_u128(&mut self, n: u128) -> Result<()>

Writes an unsigned 128-bit integer to the underlying writer.

Errors

This method propagates any error recieved from the internal call to Write::write_all.

Examples

use std::io;
use byte_order::{ByteOrder, NumberWriter};

fn main() -> io::Result<()> {
    let n = 0x12345678901234567890123456789012u128;

    let mut be_writer = NumberWriter::with_order(ByteOrder::BE, vec![]);
    be_writer.write_u128(n)?;
    assert_eq!(
        be_writer.into_inner(),
        vec![
            0x12, 0x34, 0x56, 0x78, 0x90, 0x12, 0x34, 0x56,
            0x78, 0x90, 0x12, 0x34, 0x56, 0x78, 0x90, 0x12,
        ]
    );

    let mut le_writer = NumberWriter::with_order(ByteOrder::LE, vec![]);
    le_writer.write_u128(n)?;
    assert_eq!(
        le_writer.into_inner(),
        vec![
            0x12, 0x90, 0x78, 0x56, 0x34, 0x12, 0x90, 0x78,
            0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12
        ]
    );

    Ok(())
}

pub fn write_i128(&mut self, n: i128) -> Result<()>

Writes a signed 128-bit integer to the underlying writer.

Errors

This method propagates any error recieved from the internal call to Write::write_all.

Examples

use std::io;
use byte_order::{ByteOrder, NumberWriter};

fn main() -> io::Result<()> {
    let n = 0x12345678901234567890123456789012i128;

    let mut be_writer = NumberWriter::with_order(ByteOrder::BE, vec![]);
    be_writer.write_i128(n)?;
    assert_eq!(
        be_writer.into_inner(),
        vec![
            0x12, 0x34, 0x56, 0x78, 0x90, 0x12, 0x34, 0x56,
            0x78, 0x90, 0x12, 0x34, 0x56, 0x78, 0x90, 0x12,
        ]
    );

    let mut le_writer = NumberWriter::with_order(ByteOrder::LE, vec![]);
    le_writer.write_i128(n)?;
    assert_eq!(
        le_writer.into_inner(),
        vec![
            0x12, 0x90, 0x78, 0x56, 0x34, 0x12, 0x90, 0x78,
            0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12
        ]
    );

    Ok(())
}

pub fn write_f32(&mut self, n: f32) -> Result<()>

Writes a IEEE754 single-precision floating point number to the underlying writer.

Errors

This method propagates any error recieved from the internal call to Write::write_all.

Examples

use std::io::{self, Cursor};
use byte_order::{ByteOrder, NumberWriter};

fn main() -> io::Result<()> {
    let n = 12.5f32;

    let mut be_writer = NumberWriter::with_order(ByteOrder::BE, vec![]);
    be_writer.write_f32(n)?;
    assert_eq!(be_writer.into_inner(), vec![0x41, 0x48, 0x00, 0x00]);

    let mut le_writer = NumberWriter::with_order(ByteOrder::LE, vec![]);
    le_writer.write_f32(n)?;
    assert_eq!(le_writer.into_inner(), vec![0x00, 0x00, 0x48, 0x41]);

    Ok(())
}

pub fn write_f64(&mut self, n: f64) -> Result<()>

Writes a IEEE754 double-precision floating point number to the underlying writer.

Errors

This method propagates any error recieved from the internal call to Write::write_all.

Examples

use std::io::{self, Cursor};
use byte_order::{ByteOrder, NumberWriter};

fn main() -> io::Result<()> {
    let n = 12.5f64;

    let mut be_writer = NumberWriter::with_order(ByteOrder::BE, vec![]);
    be_writer.write_f64(n)?;
    assert_eq!(be_writer.into_inner(), vec![0x40, 0x29, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]);

    let mut le_writer = NumberWriter::with_order(ByteOrder::LE, vec![]);
    le_writer.write_f64(n)?;
    assert_eq!(le_writer.into_inner(), vec![0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x29, 0x40]);

    Ok(())
}

Trait Implementations

impl<W: Write> Write for NumberWriter<W>

fn write(&mut self, buf: &[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.