Function CSTL_u32string_insert_substr

pub unsafe extern "C" fn CSTL_u32string_insert_substr(
    instance: CSTL_UTF32StringRef,
    where_: *const char32_t,
    other: CSTL_UTF32StringCRef,
    other_off: usize,
    count: usize,
    alloc: *mut CSTL_Alloc,
) -> *mut char32_t

Inserts the substring at offset other_off in other with the length given by count at the pointer where in instance.

If other_off is outside of the range [other, other + CSTL_u32string_size(other)] or if the length of the resulting string is greater than CSTL_u32string_max_size() this function has no effect and returns NULL, otherwise it returns a pointer to the first inserted character.

The pointer where must be valid and dereferenceable on instance.