castflip 0.1.14

Library for encoding/decoding numeric variables, arrays and structures in little-endian and big-endian
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How to convert between bytes and an array of `struct`s

Both an array of a regular `struct` type (with named fields) and an
array of a tuple `struct` type (with unnamed fields) can be converted.
However, only an array of a regular `struct` type is converted in the
examples below.

# 1. Converting Bytes to an array of `Struct`s

The example below *encast*s[^encast] a byte representation of an array
of struct `Coord` in big-endian ([`BE`]) as a value of an array of
struct `Coord` in native-endian by using method
[`EncastMem::encastf`].

```rust
# fn main() {
use castflip::{BE, Cast, EncastMem, Flip};

#[repr(C)]
#[derive(Cast, Flip)]
struct Coord {
    x: u16,
    y: u16,
}

let in_bytes: [u8; 8] = [0x12, 0x34, 0x56, 0x78, 0x9a, 0xbc, 0xde, 0xf0];
let out_coords: [Coord; 2] = in_bytes.encastf(BE).unwrap();
assert_eq!(out_coords[0].x, 0x1234);
assert_eq!(out_coords[0].y, 0x5678);
assert_eq!(out_coords[1].x, 0x9abc);
assert_eq!(out_coords[1].y, 0xdef0);
# }
```

In the case where an input byte representation is in native-endian,
method [`EncastMem::encast`] can be used instead.

# 2. Converting an array of `Struct`s to Bytes

The example below *decast*s[^decast] a value of an array of struct
`Coord` in native-endian as a byte representation of an array of
struct `Coord` in big-endian ([`BE`]) by using method
[`DecastMem::decastf`].

```rust
# fn main() {
use castflip::{BE, Cast, DecastMem, Flip};

#[repr(C)]
#[derive(Cast, Flip)]
struct Coord {
    x: u16,
    y: u16,
}

let in_coords = [Coord {x: 0x8765, y: 0x4321}, Coord {x: 0x0fed, y: 0xcba9}];
let mut out_bytes: [u8; 8] = [0; 8];
out_bytes.decastf(&in_coords, BE).unwrap();
assert_eq!(out_bytes, [0x87, 0x65, 0x43, 0x21, 0x0f, 0xed, 0xcb, 0xa9]);
# }
```

In the case where an output byte representation is in native-endian,
method [`DecastMem::decast`] can be used instead.

[^encast]: In this crate, to *encast* means to cast a byte
representation of a type as a value of the type.

[^decast]: In this crate, to *decast* means to cast a value of a type
as a byte representation of the type.