Каков наилучший (идиоматический) способ объединения строк в Groovy?

Опция 1:

calculateAccountNumber(bank, branch, checkDigit, account) {
    bank + branch + checkDigit + account
}

Вариант 2:

calculateAccountNumber(bank, branch, checkDigit, account) {
    "$bank$branch$checkDigit$account"
}

Я нашел интересный момент по этой теме на старом веб-сайте Groovy: вещи, которые вы можете сделать, но лучше отменить.

As in Java, you can concatenate Strings with the "+" symbol. But Java only needs that one of the two items of a "+" expression to be a String, no matter if it's in the first place or in the last one. Java will use the toString() method in the non-String object of your "+" expression. But in Groovy, you just should be safe the first item of your "+" expression implements the plus() method in the right way, because Groovy will search and use it. In Groovy GDK, only the Number and String/StringBuffer/Character classes have the plus() method implemented to concatenate strings. To avoid surprises, always use GStrings.