Trait FromBytes

pub trait FromBytes: Sized {
    type Bytes: NumBytes + ?Sized;

    // Required methods
    fn from_be_bytes(bytes: &Self::Bytes) -> Self;
    fn from_le_bytes(bytes: &Self::Bytes) -> Self;

    // Provided method
    fn from_ne_bytes(bytes: &Self::Bytes) -> Self { ... }
}

Required Associated Types

type Bytes: NumBytes + ?Sized

Required Methods

fn from_be_bytes(bytes: &Self::Bytes) -> Self

Create a number from its representation as a byte array in big endian.

Examples

use num_traits::FromBytes;

let value: u32 = FromBytes::from_be_bytes(&[0x12, 0x34, 0x56, 0x78]);
assert_eq!(value, 0x12345678);

fn from_le_bytes(bytes: &Self::Bytes) -> Self

Create a number from its representation as a byte array in little endian.

Examples

use num_traits::FromBytes;

let value: u32 = FromBytes::from_le_bytes(&[0x78, 0x56, 0x34, 0x12]);
assert_eq!(value, 0x12345678);

Provided Methods

fn from_ne_bytes(bytes: &Self::Bytes) -> Self

Create a number from its memory representation as a byte array in native endianness.

As the target platform’s native endianness is used, portable code likely wants to use from_be_bytes or from_le_bytes, as appropriate instead.

Examples

use num_traits::FromBytes;

#[cfg(target_endian = "big")]
let bytes = [0x12, 0x34, 0x56, 0x78];

#[cfg(target_endian = "little")]
let bytes = [0x78, 0x56, 0x34, 0x12];

let value: u32 = FromBytes::from_ne_bytes(&bytes);
assert_eq!(value, 0x12345678)

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl FromBytes for f32

type Bytes = [u8; 4]

fn from_be_bytes(bytes: &Self::Bytes) -> Self

fn from_le_bytes(bytes: &Self::Bytes) -> Self

fn from_ne_bytes(bytes: &Self::Bytes) -> Self

impl FromBytes for f64

type Bytes = [u8; 8]

fn from_be_bytes(bytes: &Self::Bytes) -> Self

fn from_le_bytes(bytes: &Self::Bytes) -> Self

fn from_ne_bytes(bytes: &Self::Bytes) -> Self

impl FromBytes for i8

type Bytes = [u8; 1]

fn from_be_bytes(bytes: &Self::Bytes) -> Self

fn from_le_bytes(bytes: &Self::Bytes) -> Self

fn from_ne_bytes(bytes: &Self::Bytes) -> Self

impl FromBytes for i16

type Bytes = [u8; 2]

fn from_be_bytes(bytes: &Self::Bytes) -> Self

fn from_le_bytes(bytes: &Self::Bytes) -> Self

fn from_ne_bytes(bytes: &Self::Bytes) -> Self

impl FromBytes for i32

type Bytes = [u8; 4]

fn from_be_bytes(bytes: &Self::Bytes) -> Self

fn from_le_bytes(bytes: &Self::Bytes) -> Self

fn from_ne_bytes(bytes: &Self::Bytes) -> Self

impl FromBytes for i64

type Bytes = [u8; 8]

fn from_be_bytes(bytes: &Self::Bytes) -> Self

fn from_le_bytes(bytes: &Self::Bytes) -> Self

fn from_ne_bytes(bytes: &Self::Bytes) -> Self

impl FromBytes for i128

type Bytes = [u8; 16]

fn from_be_bytes(bytes: &Self::Bytes) -> Self

fn from_le_bytes(bytes: &Self::Bytes) -> Self

fn from_ne_bytes(bytes: &Self::Bytes) -> Self

impl FromBytes for isize

type Bytes = [u8; 8]

fn from_be_bytes(bytes: &Self::Bytes) -> Self

fn from_le_bytes(bytes: &Self::Bytes) -> Self

fn from_ne_bytes(bytes: &Self::Bytes) -> Self

impl FromBytes for u8

type Bytes = [u8; 1]

fn from_be_bytes(bytes: &Self::Bytes) -> Self

fn from_le_bytes(bytes: &Self::Bytes) -> Self

fn from_ne_bytes(bytes: &Self::Bytes) -> Self

impl FromBytes for u16

type Bytes = [u8; 2]

fn from_be_bytes(bytes: &Self::Bytes) -> Self

fn from_le_bytes(bytes: &Self::Bytes) -> Self

fn from_ne_bytes(bytes: &Self::Bytes) -> Self

impl FromBytes for u32

type Bytes = [u8; 4]

fn from_be_bytes(bytes: &Self::Bytes) -> Self

fn from_le_bytes(bytes: &Self::Bytes) -> Self

fn from_ne_bytes(bytes: &Self::Bytes) -> Self

impl FromBytes for u64

type Bytes = [u8; 8]

fn from_be_bytes(bytes: &Self::Bytes) -> Self

fn from_le_bytes(bytes: &Self::Bytes) -> Self

fn from_ne_bytes(bytes: &Self::Bytes) -> Self

impl FromBytes for u128

type Bytes = [u8; 16]

fn from_be_bytes(bytes: &Self::Bytes) -> Self

fn from_le_bytes(bytes: &Self::Bytes) -> Self

fn from_ne_bytes(bytes: &Self::Bytes) -> Self

impl FromBytes for usize

type Bytes = [u8; 8]

fn from_be_bytes(bytes: &Self::Bytes) -> Self

fn from_le_bytes(bytes: &Self::Bytes) -> Self

fn from_ne_bytes(bytes: &Self::Bytes) -> Self

Implementors