Macro concat_bytes 

macro_rules! concat_bytes {
    ($($e:literal),+ $(,)?) => { ... };
}

🔬This is a nightly-only experimental API. (concat_bytes #87555)

Concatenates literals into a byte slice.

This macro takes any number of comma-separated literals, and concatenates them all into one, yielding an expression of type &[u8; _], which represents all of the literals concatenated left-to-right. The literals passed can be any combination of:

• byte literals (b'r')
• byte strings (b"Rust")
• arrays of bytes/numbers ([b'A', 66, b'C'])

Examples

#![feature(concat_bytes)]

let s: &[u8; 6] = concat_bytes!(b'A', b"BC", [68, b'E', 70]);
assert_eq!(s, b"ABCDEF");