!  The MultiAdd routine adds object "o" to the multiple-object-list.
!
!  This is only allowed to hold 63 objects at most, at which point it ignores
!  any new entries (and sets a global flag so that a warning may later be
!  printed if need be).
! ----------------------------------------------------------------------------

[ MultiAdd o i j;
  i=multiple_object-->0;
  if (i==63) { toomany_flag=1; rtrue; }
  for (j=1:j<=i:j++)
      if (o==multiple_object-->j) 
          rtrue;
  i++;
  multiple_object-->i = o;
  multiple_object-->0 = i;
];