This alias is to leave (part) all channels that have +u mode includes in their modes.
Do not work the comparator.
I've done wrong?
Code:
alias modeu {
  var %m = $chan(0)
  while ( %m > 0 ) {
    if ($me ison $chan(%m)) && ($chan($chan).mode isin u) {
      .part $chan(%m)
    }
    dec %m
  }
}