Backtracking Problem
- by Joshua Green
Could someone please guide me through backtracking in Prolog-C using the simple example below?
Here is my Prolog file:
likes( john, mary ).
likes( john, emma ).
likes( john, ashley ).
Here is my C file:
#include...
term_t tx;
term_t tv;
term_t goal_term;
functor_t goal_functor;
int main( int argc, char** argv )
{
argv[0] = "libpl.dll";
PL_initialise( argc, argv );
PlCall( "consult( swi( 'plwin.rc' ) )" );
PlCall( "consult( 'likes.pl' )" );
tv = PL_new_term_ref( );
PL_put_atom_chars( tv, "john" );
tx = PL_new_term_ref( );
goal_term = PL_new_term_ref( );
goal_functor = PL_new_functor( PL_new_atom( "likes" ), 2 );
PL_cons_functor( goal_term, goal_functor, tv, tx );
PlQuery q( "likes", ??? );
while ( q.next_solution( ) )
{
char* solution;
PL_get_atom_chars( tx, &solution );
cout << solution << endl;
}
PL_halt( PL_toplevel() ? 0 : 1 );
}
What should I replace ??? with?
Or is this the right approach to get all the backtracking results generated and printed?
Thank you,
