How to not do anything on the "rest case" when matching a string?

Question

I have a string where I want to check if it's a semicolon, comma or colon. If it's not any of those, I don't want to do anything:

match token.as_ref() {
    ";" => semicolons += 1,
    "," => commas += 1,
    ":" => colons += 1,
     _ => println!(""),
}

This works, but I don't really want to print a bunch of empty lines (cause a lot of the tokens don't match these criteria).

What would be the most correct way to solve this?

Answer 1

let some_u8_value = 0u8;
match some_u8_value {
    1 => println!("one"),
    3 => println!("three"),
    5 => println!("five"),
    7 => println!("seven"),
    _ => (),
}

The () is just the unit value, so nothing will happen in the _ case. As a result, we can say that we want to do nothing for all the possible values that we don’t list before the _ placeholder.

You can also use empty block expression {}.