Re: How to use the Global variables on the GNU Prolog ?

[Vic Bancroft]

Simple User wrote:

> How to use the Global variables on the GNU Prolog?
>  
If you intend to have a prolog database, then the most natural fit might 
be to assert literals.  Just use a dynamic/1 directive and simply assert 
and retract them.

   :- dynamic( atom_counter/2 ).

   /** counters( +Name, -Number )
   *
   * Given an atom, records an incrementing number, begining with zero.
   *
   */
   counters( Name, Number ) :-
   atom_counter( Name, LastNumber ),
   retract( atom_counter( Name, LastNumber ) ),
   Number is LastNumber + 1,
   assertz( atom_counter( Name, Number ) ),
   !.

   counters( Name, 0 ) :-
   assertz( atom_counter( Name, 0 ) ),
   !.

> I want a sample.
>  
For more context you are welcome to read,

   http://elvis.dlogic.org/~bancroft/pub/gplfaq/faq_parse.pl

more,
l8r,
v