l">Trail</A> *trp);
</B></PRE>This routine checks if <A HREF="term.html">Term</A> t2 (without a <A HREF="unify.html">Context</A>) is an
instance of <A HREF="term.html">Term</A> t1 (in <A HREF="unify.html">Context</A> c1).
If successful, <A HREF="unify.html">Context</A> c1 and <A HREF="unify.html">Trail</A> * trp are updated.
The calling sequence and the use of Contexts and Trails is similar
to those for <A HREF="#unify">unify</A>().
<A NAME="match_weight"></A><HR><PRE><B>BOOL match_weight(<A HREF="term.html