$ perl -MO=Deparse -e '(!(($a != 3) || ($a != 77) || ($a != 8)))' not $a != 3 || $a != 77 || $a != 8; -e syntax OK $ perl -E '$a = 77; if (not $a != 3 || $a != 77 || $a != 8) { say "not" } else { say "is" }' is