Consider how this project would use const-generics before 1.0 release

[Luro02]

Once const-generics are further stabilized, one could write an encode/decode function that does not error:

#![feature(const_generics, const_evaluatable_checked)]
use std::array::IntoIter;

const HEX_CHARS_LOWER: &[u8; 16] = b"0123456789abcdef";

fn generate_iter(len: usize) -> impl Iterator<Item = (usize, usize)> {
    (0..len).step_by(2).zip((0..len).skip(1).step_by(2))
}

const fn byte2hex(byte: u8, table: &[u8; 16]) -> (u8, u8) {
    let high = table[((byte & 0xf0) >> 4) as usize];
    let low = table[(byte & 0x0f) as usize];

    (high, low)
}

pub fn encode<const N: usize>(bytes: [u8; N]) -> [u8; N * 2] {
    let mut output = [0; { N * 2 }];

    for (byte, (i, j)) in IntoIter::new(bytes).zip(generate_iter(N * 2)) {
        let (high, low) = byte2hex(byte, HEX_CHARS_LOWER);
        output[i] = high;
        output[j] = low;
    }

    output
}

fn main() {
    assert_eq!(encode(*b"kiwi"), *b"6b697769");
}

playground

I think this should be considered before the 1.0 release (this could either be a new function or it could replace an existing one?).