A HREF="term.html">Term</A> t);
</B></PRE>Reverse a listterm.  A new list structure is created, but
the members are not copied.  The old list structure is freed.
<A NAME="listterm_to_tlist"></A><HR><PRE><B>Plist listterm_to_tlist(<A HREF="term.html">Term</A> t);
</B></PRE>Given a proper listterm (e.g, [a,b,c]), return a Plist
of the members.  The members are not copied.
<A NAME="listterm_zap"></A><HR><PRE><B>void listterm_zap(<A HREF="term.html">Term</A> t);
</B></PRE>Free a list structure, but do not free 