Re: Bit rotation question/challenge

[Afgdr via Digitalmars-d-learn]

On Saturday, 30 January 2021 at 13:30:49 UTC, burt wrote:

I have a static array of `ubyte`s of arbitrary size:

```d
ubyte[4] x = [ // in reality, ubyte[64]
    0b00001000,
    0b00000001,
    0b00010101,
    0b11110010,
];
```

Now I want to bit-rotate the array as if it is one big integer. So:

```d

ubyte[n] rotateRight(size_t n)(ref const ubyte[n] array, uint rotation)

{
    // ?
}
// same for rotateLeft

ubyte[4] y = [
    0b11111001,
    0b00000100,
    0b00000000,
    0b10001010,
];
assert(x.rotateRight(9) == y);
assert(y.rotateLeft(9) == x);
```

Any ideas how this could be achieved? I.e. what should go at the "?" for rotateRight and rotateLeft?

cast as uint and shift. cast the result as ubyte[4].