Rust const_str_eq

const_str_eq.rs

pub const fn const_str_eq(a: &str, b: &str) -> bool {
    if a.as_bytes().len() != b.as_bytes().len() {
        return false;
    }
    let mut i = 0;
    while i < a.as_bytes().len() {
        if a.as_bytes()[i] != b.as_bytes()[i] {
            return false;
        }
        i += 1;
    }
    true
}

#[test]
fn test_const_str_eq() {
    const ARE_THEY: bool = const_str_eq("hello", "world");
    assert_eq!(ARE_THEY, false);
    const ARE_THEY2: bool = const_str_eq("hello world", "hello world");
    assert_eq!(ARE_THEY2, true);
    const ARE_THEY3: bool = const_str_eq("hello_world", "hello world");
    assert_eq!(ARE_THEY3, false);
}

(can't use for loops in const context, so we we manually increment i in a while loop)