What is the idiomatic way of looping through the bytes of an integer number in Rust?

Question

I tried such a piece of code to loop through the bytes of a u64:

let mut message: u64 = 0x1234123412341234;
let msg = &message as *mut u8;

for b in 0..8 {
    // ...some work...
}

Unfortunately, Rust doesn't allow such C-like indexing.

Answer 1

While transmute-ing is possible (see @Tim's answer), it is better to use the byteorder crate to guarantee endianness:

extern crate byteorder;

use byteorder::ByteOrder;

fn main() {
    let message = 0x1234123412341234u64;
    let mut buf = [0; 8];
    byteorder::LittleEndian::write_u64(&mut buf, message);

    for b in &buf {
         // 34, 12, 34, 12, 34, 12, 34, 12, 
         print!("{:X}, ", b);
    }

    println!("");

    byteorder::BigEndian::write_u64(&mut buf, message);

    for b in &buf {
         // 12, 34, 12, 34, 12, 34, 12, 34, 
         print!("{:X}, ", b);
    }
}

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