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: hello_rant.rs
    path of file: ./repos/rant/examples
    
    the code of the file until where you have to start completion: use rant::Rant;
use std::error::Error;

fn main() -> Result<(), Box<dyn Error>> {
  // Create a Rant context and load the standard library
  let mut rant = Rant::with_random_seed();

  // Compile a simple program
  let program = rant.compile_quiet(r#"
  [$greet:name] {
    {Hello|Hi|H
    
fn main() -> Result<(), Box<dyn Error>> {
  // Create a Rant context and load the standard library
  let mut rant = Rant::with_random_seed();

  // Compile a simple program
  let program = rant.compile_quiet(r#"
  [$greet:name] {
    {Hello|Hi|Hey} <name>!
  }
  [greet:world]
  "#)?;

  // Run the program and fetch the result string
  let output = rant.run(&program)?;
  println!("{}", output);
  Ok(())
}