While loop is easier and takes fewer bytes and the end result
would be looping no matter the method.
if ($1 && $2) could be if $2
echo -a $+($chr(3),12, /massinvite: insufficient parameters)
could be
echo 12 -a /massinvite: insufficient parameters

alias massinvite { if $2 { var %i 1 | while $nick($1,%i) { echo # invite $v1 $2 | inc %i } } | else { echo 12 -a * /massinvite: insufficient parameters) } }