Category : Files from Magazines
Archive   : AIJUN87.ZIP
Filename : TOOL2.LTG

 
Output of file : TOOL2.LTG contained in archive : AIJUN87.ZIP

EXPERT TOOLBOX LISTING 2

/* Pretend we have an expert data base with lots of general world */
/* knowledge built in. This knowledge is stored in Arity's "default */
/* world," and no unusual PROLOG syntax has been necessary. Now we */
/* want to add a large amount of domain-specific knowledge about, say,*/
/* all the cases of meningitis in the country. To separate this */
/* knowledge from the rest of the system, we first create a new world.*/

create_world(meningitis).
yes

/* Now we make our new world the current data world, replacing */
/* "ari," the name of Arity's default world. */

data_world(X,meningitis).
X = ari
yes

/* All assertions and queries will now be performed in the */
/* meningitis world. There are several useful predicates */
/* for managing the worlds. These are listed below. */

default_world(X) /* Makes X the default world */
what_worlds(X) /* Lists the worlds currently in existence */
save(Filename) /* Saves the state of all the worlds to disk */
restore /* Eliminates all changes made to all worlds */
/* since the last time they were saved */
restore(Filename) /* Loads the program state from a SAVED file */
delete_world(X) /* Eliminates a world, with all it contains */

/* Predicates that search the data base look only in the current */
/* default world. A simple definition provides a way to search */
/* through a list of worlds (taken from Arity documentation). */

data_search([World|_],Key,Term) :-
data_world(_,World), /* Is World a data world? */
recorded(Key,Term,_). /* Search for Term recorded
data_search([_|Tail],Key,Term© :- /ª undeò Key® */
data_search(Tail,Key,Term).


  3 Responses to “Category : Files from Magazines
Archive   : AIJUN87.ZIP
Filename : TOOL2.LTG

  1. Very nice! Thank you for this wonderful archive. I wonder why I found it only now. Long live the BBS file archives!

  2. This is so awesome! 😀 I’d be cool if you could download an entire archive of this at once, though.

  3. But one thing that puzzles me is the “mtswslnkmcjklsdlsbdmMICROSOFT” string. There is an article about it here. It is definitely worth a read: http://www.os2museum.com/wp/mtswslnk/