cmd.add
#6816
Content:
$love add *:@pemit %#=
[color(196,69,Love Calculator)] says:%r[ifelse(hastype(*%0,player),
 [ifelse(not(hasattr(#6816,USER_%0)),
  Adding to the list: %0 [set(#6816,USER_%0:0)],
  Already on the list.
  )],
  %0 is not a player.
)]


One line version:

$love add *:@pemit %#=[color(196,69,Love Calculator)] says:%r[ifelse(hastype(*%0,player),[ifelse(not(hasattr(#6816,USER_%0)),Adding to the list: %0 [set(#6816,USER_%0:0)],Already on the list.)],%0 is not a player.)]