Hello World

Some basic example:

fn main() {
    println!("Hello World!");
    eprintln!("Message in stderr :-(");
}

Some more complex example:

fn main() {
    let hello = "Hello, world";
    println!("{}", hello);
}

On last more, a little more hard-core:

fn main() {
    println!("{}",
             "Hello, world"
                .chars()
                .collect::<Vec<char>>()
                .into_iter()
                .collect::<String>()
    );
}