Something

alias clearbans {
  if ($me isop $chan) {
    echo $active Clearing bans on $chan
    var %i = 1, %bans
    while (%i <= $ibl($chan,0)) {
      %bans = %bans $ibl($chan,%i)
      if ($numtok(%bans,32) == $modespl) {
        mode $chan - $+ $str(b,$numtok(%bans,32)) %bans
        %bans = ""
      }
      inc %i
    }
    if (%bans) mode $chan - $+ $str(b,$numtok(%bans,32)) %bans
  }
}