XSB Src (SVN)-old

making abolish_table_subgoal(s) standard.

Added abolish_table_subgoal and abolish_table_subgoals

Apparently this wasn't i svn.

Apparently also forgot to add these...

Forgot to add these earlier.

Updated tests for new version of transitive abolishes.

Minor changes writing lettervars, and op precedence of +,
and updating xwams, which I hope will now be less variable.

Changed compiler to use internal cmp_gensym, and not global gensym,
which was causing internally generated names (by specialization) to
vary depending on the context of the compile, and making xwams differ
unnecessarily.

Cosmetic change of the name of a macro.

Major change to transitive abolishes for calls. As before, if a
table T_a is abolished, any table T' that has an answer that
depends on T_a or an answer in T_a is abolished. Now, any table
T'' upon which T_a depends (i.e., T_a has an answer that has T''
or an answer in T'' in its delay list) is affected in the
following manner. Any backpointers from T'' to T_a are removed
from the subgoal or answer PNDEs. This means that after table
abolishes, all backpointers from non-abolished tables will remain
valid. (At least, I sure hope so.)

In the first version of transitive abolishes, tables such as T''
were unaffected. However, this left invalid back pointers and
led to core dumps when running Ergo. The next version that was
has been in place for a couple of weeks actually abolished tables
such as T'', but this was too extreme. So hopefully this version
will be just right.

The above changes were in tr_utils.c. The slgdelay* changes were so that remove_pndes could be
used in tr_utils.c