Alternate Style

There will be times when we need to use an alternate syntax for printing. Instead of this:

println!("alfa is {alfa}");

the alternate style uses an empty set of {} curly brackets inside the quotes with the variable name outside them and separated by a comma like this:

println!("alfa is {}", alfa);

A full program looks like this:

fn main() {
  let alfa = String::from("apple");
  println!("alfa is {}", alfa);
}

which outputs:

alfa is apple

TODO

• add note about why that change is necessary