tables.h

/* File:      tables.h
** Author(s): Johnson, Swift, Sagonas, Rao, Freire
** Contact:   xsb-contact@cs.sunysb.edu
** 
** Copyright (C) The Research Foundation of SUNY, 1986, 1993-1998
** 
** XSB is free software; you can redistribute it and/or modify it under the
** terms of the GNU Library General Public License as published by the Free
** Software Foundation; either version 2 of the License, or (at your option)
** any later version.
** 
** XSB is distributed in the hope that it will be useful, but WITHOUT ANY
** WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
** FOR A PARTICULAR PURPOSE.  See the GNU Library General Public License for
** more details.
** 
** You should have received a copy of the GNU Library General Public License
** along with XSB; if not, write to the Free Software Foundation,
** Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
**
** $Id: tables.h,v 1.12 2006/01/12 21:33:52 tswift Exp $
** 
*/


#ifndef __TABLES_H__

#define __TABLES_H__


/*===========================================================================*/

/*
 *                    Tabling Function Prototypes
 *                    ===========================
 */

void    table_call_search(CTXTdeclc TabledCallInfo *, CallLookupResults *);
BTNptr  table_answer_search(CTXTdeclc VariantSF, int, int, CPtr, xsbBool *);
void    table_consume_answer(CTXTdeclc BTNptr, int, int, CPtr, TIFptr);
ALNptr  table_identify_relevant_answers(CTXTdeclc SubProdSF, SubConsSF, CPtr);
void    table_complete_entry(CTXTdeclc VariantSF);

void    release_all_tabling_resources(CTXTdecl);
VariantSF NewProducerSF(CTXTdeclc BTNptr,TIFptr);

/*
 * The next answer to consume is obtained from the old answer continuation.
 * The new answer continuation is the old continuation but with this answer
 * removed.
 */

#define table_pending_answer( OldAnswerContinuation,                    \
                              NewAnswerContinuation,                    \
                              NextAnswer,                               \
                              Consumer,                                 \
                              Producer,                                 \
                              AnswerTemplate,                           \
                              PreIdentificationOp,                      \
                              PostIdentificationOp ) {                  \
                                                                        \
   NewAnswerContinuation = ALN_Next(OldAnswerContinuation);             \
                                                                        \
   if ( IsNULL(NewAnswerContinuation) && IsProperlySubsumed(Consumer) ) \
     if ( MoreAnswersAreAvailable(Consumer,Producer) ) {                \
       /* printf("make ans list for :"); sfPrintGoal(CTXTdeclc stddbg, Consumer, FALSE); */  \
       PreIdentificationOp;                                             \
       NewAnswerContinuation =                                          \
         table_identify_relevant_answers(CTXTc Producer, Consumer,      \
                                         AnswerTemplate);               \
       PostIdentificationOp;                                            \
     }                                                                  \
   if ( IsNonNULL(NewAnswerContinuation) )                              \
     NextAnswer = ALN_Answer(NewAnswerContinuation);                    \
   else                                                                 \
     NextAnswer = NULL;                                                 \
 }


/*
 * Used as an argument to table_pending_answer() when no pre- or post-
 * identification operation is required.
 */

#define TPA_NoOp


/*
 * Determines whether a producer subgoal has added answers to its set
 * since the given consumer last collected relevant answers from that set.
 */

#define MoreAnswersAreAvailable(ConsSF,ProdSF)                  \
   ( IsNonNULL(subg_ans_root_ptr(ProdSF)) &&                    \
     (TSTN_TimeStamp((TSTNptr)subg_ans_root_ptr(ProdSF)) >      \
      conssf_timestamp(ConsSF)) )


/*===========================================================================*/


#endif

---