You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: rid.rs
    path of file: ./repos/gdnative/gdnative-core/src/core_types
    
    the code of the file until where you have to start completion: use crate::private::get_api;
use crate::sys;
u
    
    fn to_u64(self) -> u64 {
        unsafe {
            // std::mem::transmute needs source and destination types to have the same size. On 32
            // bit systems sizeof(void *) != size_of<u64>() so this fails to compile. The bindings
            // define godot_rid as (a newtype of) [u8; u8size] or [u8; u4size] depending on
            // architecture word size so transmuting to usize should always work.
            transmute::<_, usize>(self.0) as _
        }
    }