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: main.rs
    path of file: ./repos/gnvim/ui/src
    
    the code of the file until where you have to start completion: use glib::ExitCode;
use gtk::{gio, pango, prelude::*};

mod api;
mod arguments;
mod boxed;
mod child_iter;
mod colors;
mod components;
mod font;
mod input;
mod macros;
mod math;
mod nvim;
mod render;

use components::appwindow::AppWindow;

pub const SCALE: f32 = pango::SCAL
    
fn main() -> ExitCode {
    gio::resources_register_include!("gnvim.gresource").expect("Failed to register resources.");

    let args = arguments::Arguments::parse();

    let mut flags = gio::ApplicationFlags::empty();
    flags.insert(gio::ApplicationFlags::NON_UNIQUE);
    flags.insert(gio::ApplicationFlags::HANDLES_OPEN);

    let app = gtk::Application::builder()
        .application_id("com.github.vhakulinen.gnvim")
        .flags(flags)
        .build();

    app.connect_activate(move |app| build_ui(app, &args));

    // NOTE(ville): Pass empty arguments to the gtk application. We handle
    // those manually.
    app.run_with_args::<&str>(&[])
}