Function croaring_sys::roaring_bitmap_select

pub unsafe extern "C" fn roaring_bitmap_select(
    r: *const roaring_bitmap_t,
    rank: u32,
    element: *mut u32
) -> bool

Selects the element at index ‘rank’ where the smallest element is at index 0. If the size of the roaring bitmap is strictly greater than rank, then this function returns true and sets element to the element of given rank. Otherwise, it returns false.