Function rfind

rust/stringzilla.rs:1371–1389

(haystack: H, needle: N)

/// within `haystack` if found, otherwise `None`.
#[inline(always)]
pub fn rfind<H, N>(haystack: H, needle: N) -> Option<usize>
where
    H: AsRef<[u8]>,
    N: AsRef<[u8]>,
{
    let haystack_ref = haystack.as_ref();
    let needle_ref = needle.as_ref();
    let haystack_pointer = haystack_ref.as_ptr() as _;
    let haystack_length = haystack_ref.len();
    let needle_pointer = needle_ref.as_ptr() as _;
    let needle_length = needle_ref.len();
    let result = unsafe { sz_rfind(haystack_pointer, haystack_length, needle_pointer, needle_length) };

    if result.is_null() {
        None
    } else {
        Some(unsafe { result.offset_from(haystack_pointer) }.try_into().unwrap())
    }
}

/// Finds the index of the first character in `haystack` that is also present in `needles`.
/// This function is particularly useful for parsing and tokenization tasks where a set of