In const, how do I replace \n multiple times with ""?

help
1

I have this code over here:

    const CMP: &str = "should";
    const VALUE: &str = "should \n have\nshoulds";

    const FINAL_VALUE: &str = const_str::replace!(VALUE, "\n", "");

const_str is a library: const_str - Rust

Unfortunately const FINAL_VALUE: &str = const_str::replace!(VALUE, "\n", ""); will run once, and won't remove all the \n enter characters.

The idea is that during compile time I want to split by line and then split by space and determine if certain words exist or not.

2

Not the prettiest, but it strips newline characters from a string slice:

const VALUE: &str = "should \n have\nshoulds";

const FINAL_VALUE_BYTES: [u8; len_without_newline(VALUE)] = bytes_without_newline(VALUE);

const FINAL_VALUE: &str = match std::str::from_utf8(&FINAL_VALUE_BYTES) {
    Ok(res) => res,
    Err(_) => panic!(),
};

const fn len_without_newline(s: &str) -> usize {
    let s = s.as_bytes();

    let mut i_val = 0;
    let mut i_res = 0;

    while i_val < s.len() {
        if s[i_val] != '\n' as u8 {
            i_res += 1;
        }
        i_val += 1;
    }

    i_res
}

const fn bytes_without_newline<const N: usize>(s: &str) -> [u8; N] {
    let s = s.as_bytes();

    let mut res = [0u8; N];

    let mut i_val = 0;
    let mut i_res = 0;

    while i_val < s.len() {
        if s[i_val] != '\n' as u8 {
            res[i_res] = s[i_val];
            i_res += 1;
        }
        i_val += 1;
    }

    res
}

fn main() {
    assert_eq!(FINAL_VALUE, "should  haveshoulds");
}

Playground.

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