When none of the match expressions are matched in a handle_message method call, by default Xip will raise a Xip::Errors::UnrecognizedMessage exception. This is typically the desired behavior because it allows the UnrecognizedMessagesController to run.
In the event that you don't want to raise an error, like in the case where you want to just save what the user typed in and move on, you can use the nil matcher.
In the above example, if a user enters a specific amount instead of choosing one of the ranges provided, we just store that amount and don't raise an error.
You may likely still want to verify the input they entered is a Numeric. There are also better ways to handle an example like this using get_match.