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: icon.rs
    path of file: ./repos/winit/src/platform_impl/linux/x11/util
    
    the code of the file until where you have to start completion: #![allow(clippy::assertions_on_constants)]

use super::*;
use crate::icon::{Pixel, RgbaIcon, PIXEL_SIZE};

impl Pixel {
    pub fn to_packed_argb(&self) -> Cardinal {
        let mut
    
    pub fn to_packed_argb(&self) -> Cardinal {
        let mut cardinal = 0;
        assert!(CARDINAL_SIZE >= PIXEL_SIZE);
        let as_bytes = &mut cardinal as *mut _ as *mut u8;
        unsafe {
            *as_bytes.offset(0) = self.b;
            *as_bytes.offset(1) = self.g;
            *as_bytes.offset(2) = self.r;
            *as_bytes.offset(3) = self.a;
        }
        cardinal
    }