 t1 and t2 identical?
<A NAME="top_flip"></A><HR><PRE><B><A HREF="term.html">Term</A> top_flip(<A HREF="term.html">Term</A> a);
</B></PRE>Given a binary term (or atom), return the flip.
The two arguments are not copied.
When done with it, call <A HREF="#zap_top_flip">zap_top_flip</A>(t) instead of
zap_term so that the arguments are not zapped.
<A NAME="unfold_order"></A><HR><PRE><B>Ordertype unfold_order(<A HREF="term.html">Term</A> alpha, <A HREF="term.html">Term</A> beta);
</B></PRE><A NAME="zap_literal_f