This is a version of what I use for the channel menu for adding, removing and joining multi channels from the channel menu

Code:
 
Channel Menu
.Auto Join : autoj
.-
.Add Auto Join Channel # : {
  if ( %autojoin1 == $null ) { set %autojoin1 1. # | goto end }
  if ( %autojoin2 == $null ) { set %autojoin2 2. # | goto end }
  if ( %autojoin3 == $null ) { set %autojoin3 3. # | goto end }
  if ( %autojoin4 == $null ) { set %autojoin4 4. # | goto end }
  if ( %autojoin5 == $null ) { set %autojoin5 5. # | goto end }
  else { echo 1 »14»15»12 You have too many channels in your channel list | halt }
  :end
  echo 1 »14»15» 4 # 12has been added to your channel list.
}
.Join Auto Set Channel
..%autojoin1:join $remove(%autojoin1,1. )
..%autojoin2:join $remove(%autojoin2,2. )
..%autojoin3:join $remove(%autojoin3,3. )
..%autojoin4:join $remove(%autojoin4,4. )
..%autojoin5:join $remove(%autojoin5,5. )
.Unset Auto Join Channel
..%autojoin1:unset %autojoin1 
..%autojoin2:unset %autojoin2 
..%autojoin3:unset %autojoin3
..%autojoin4:unset %autojoin4 
..%autojoin5:unset %autojoin5