Why that's actually a very good idea. Thank you.
Updated:

 alias characters {
  if (!$1) { 
    echo Not enough parameters.
  }
  if ($1) && ($2) && ($1 isnum) && ($2 isnum) && ($1 <= $2) { 
    var %x = $1
    while (%x <= $2) {
      echo -a Character: $chr(%x) = $+($chr(36),$chr(99),$chr(104),$chr(114),$chr(40),%x,$chr(41))
      inc %x
    } 
  }
  if ($1) && ($2) && ($1 !isnum) && ($2 !isnum) { 
    echo -a $1 and $2 aren't numbers.
  }
  if ($1) && ($1 isnum) && ($2) && ($2 !isnum) {
    echo -a $2 isn't a number, but $1 is.
  }
  if ($1) && ($1 !isnum) && ($2) && ($2 isnum) {
    echo -a $1 isn't a number, but $2 is.
  }
  if ($1) && (!$2) {
    echo Not enough parameters.
  }
  if ($1) && ($2) && ($1 isnum) && ($2 isnum) && ($1 >= $2) { 
    echo -a Sorry, $2 is smaller than $+($1,.)
  }
}