Table Directives and Declarations

Often it is tedious to decide which predicates must be tabled. To address this, XSB can automatically table predicates in files. The declaration auto_table chooses predicates to table to assist in termination, while suppl_table chooses predicates to table to optimize data-oriented queries. Both are explained in Section 3.8.4.

Exercise 5.2.7   The reader may have noted that the command table was referred to as a directive, while auto_table and suppl_table were both referred to as declarations. The difference is that the user can execute a directive at the command line but not a compiler declaration. For instance, restart XSB and at the XSB prompt, type the directive

         ?- table(dyn_path/2).

and

         ?- load_dyn(dyn_examples).

Try the queries to path/2 of the previous examples. Note that it is important to dynamically load dyn_examples.P -- otherwise the code in the file will be compiled without knowledge of the tabling declaration.