The next arg is ignored. ~n* ignores the next n arguments.
~:* backs up in the list of arguments so that the argument last processed will be processed again. ~n:* backs up n arguments.
When within a ~{ construct (see below), the ignoring (in either direction) is relative to the list of arguments being processed by the iteration.
~n@* goes to the nth arg, where 0 means the first one; n defaults to 0, so ~@* goes back to the first arg. Directives after a ~n@* will take arguments in sequence beginning with the one gone to. When within a ~{ construct, the ``goto'' is relative to the list of arguments being processed by the iteration.