Function safe_transmute::to_bytes::transmute_one_to_bytes_mut

source · 
pub fn transmute_one_to_bytes_mut<S: TriviallyTransmutable>(
    from: &mut S
) -> &mut [u8] ⓘ
Expand description

Transmute a single instance of a trivially transmutable type into a slice of its bytes.

§Examples

An u32:

// Little-endian
assert_eq!(transmute_one_to_bytes_mut(&mut 0x0123_4567),
           &mut [0x67, 0x45, 0x23, 0x01]);

An arbitrary type:

#[repr(C)]
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
struct Gene {
    x1: u8,
    x2: u8,
}
unsafe impl TriviallyTransmutable for Gene {}

let mut gene = Gene {
    x1: 0x42,
    x2: 0x69,
};

{
    let gene_data = transmute_one_to_bytes_mut(&mut gene);
    assert_eq!(gene_data, &mut [0x42, 0x69]);
    gene_data[0] = 0xB0;
}

assert_eq!(gene, Gene {
    x1: 0xB0,
    x2: 0x69,
});