Main.rs

In this section, let’s just cover the contents of main.rs, build.rs and utils.rs.

The main.rs file is the entry point of the application. Here’s the complete main.rs file:

use clap::Parser;
use cli::Cli;
use color_eyre::Result;

use crate::app::App;

mod action;
mod app;
mod cli;
mod components;
mod config;
mod errors;
mod logging;
mod tui;

#[tokio::main]
async fn main() -> Result<()> {
    crate::errors::init()?;
    crate::logging::init()?;

    let args = Cli::parse();
    let mut app = App::new(args.tick_rate, args.frame_rate)?;
    app.run().await?;
    Ok(())
}

In essence, the main function creates an instance of App and calls App.run(), which runs the “handle event -> update state -> draw” loop. We will talk more about this in a later section.

This main.rs file incorporates some key features that are not necessarily related to ratatui, but in my opinion, essential for any Terminal User Interface (TUI) program:

• Command Line Argument Parsing (clap)
• XDG Base Directory Specification
• Logging
• Panic Handler

These are described in more detail in the [config.rs], [cli.rs], [errors.rs] and [logging.rs] files.