before [zl compare] existed, you were also already able to use certain zl combinations for this kind of thing.
when looking for a string solutions (we call "strings" "symbols" in max) always look into zl, because
it treats every symbol as a list of symbols with only one element. for example [zl reg] makes a great
place not only to store "1 2 3 4 5", but also for the message "stop".