Rust const &[u8] and &str concatenation

const NUM: i128 = 1;
// &str
const HELLO: &str = "Hello";
const RES: &str = concat_const::concat!(HELLO, "world", concat_const::int!(NUM));
assert_eq!(RES, "Helloworld1");
// bytes
const HELLO: &[u8] = b"Hello";
const RES: &[u8] = concat_const::concat_bytes!(HELLO, b"world", concat_const::int_bytes!(NUM));
assert_eq!(RES, b"Helloworld1");

Look at the tests for more usage examples