rulepsr.c

clips源代码

   /*******************************************************/
   /*      "C" Language Integrated Production System      */
   /*                                                     */
   /*             CLIPS Version 6.30  10/19/06            */
   /*                                                     */
   /*                 RULE PARSING MODULE                 */
   /*******************************************************/

/*************************************************************/
/* Purpose:  Parses a defrule construct.                     */
/*                                                           */
/* Principal Programmer(s):                                  */
/*      Gary D. Riley                                        */
/*                                                           */
/* Contributing Programmer(s):                               */
/*                                                           */
/* Revision History:                                         */
/*                                                           */
/*      6.24: Removed DYNAMIC_SALIENCE, INCREMENTAL_RESET,   */
/*            and LOGICAL_DEPENDENCIES compilation flags.    */
/*                                                           */
/*      6.30: Added support for hashed alpha memories.       */
/*                                                           */
/*************************************************************/

#define _RULEPSR_SOURCE_

#include "setup.h"

#if DEFRULE_CONSTRUCT

#include <stdio.h>
#define _STDIO_INCLUDED_
#include <string.h>

#include "analysis.h"
#include "constant.h"
#include "constrct.h"
#include "cstrcpsr.h"
#include "cstrnchk.h"
#include "cstrnops.h"
#include "engine.h"
#include "envrnmnt.h"
#include "exprnpsr.h"
#include "incrrset.h"
#include "memalloc.h"
#include "pattern.h"
#include "prccode.h"
#include "prcdrpsr.h"
#include "router.h"
#include "rulebld.h"
#include "rulebsc.h"
#include "rulecstr.h"
#include "ruledef.h"
#include "ruledlt.h"
#include "rulelhs.h"
#include "scanner.h"
#include "symbol.h"
#include "watch.h"

#include "lgcldpnd.h"

#if DEFTEMPLATE_CONSTRUCT
#include "tmpltfun.h"
#endif

#if BLOAD || BLOAD_ONLY || BLOAD_AND_BSAVE
#include "bload.h"
#endif

#include "rulepsr.h"

/***************************************/
/* LOCAL INTERNAL FUNCTION DEFINITIONS */
/***************************************/

#if (! RUN_TIME) && (! BLOAD_ONLY)
   static struct expr            *ParseRuleRHS(void *,char *);
   static int                     ReplaceRHSVariable(void *,struct expr *,void *);
   static struct defrule         *ProcessRuleLHS(void *,struct lhsParseNode *,struct expr *,SYMBOL_HN *,int *);
   static struct defrule         *CreateNewDisjunct(void *,SYMBOL_HN *,int,struct expr *,
                                                    int,unsigned,struct joinNode *);
   static int                     RuleComplexity(void *,struct lhsParseNode *);
   static int                     ExpressionComplexity(void *,struct expr *);
   static int                     LogicalAnalysis(void *,struct lhsParseNode *);
   static void                    AddToDefruleList(struct defrule *);
#if DEVELOPER && DEBUGGING_FUNCTIONS
   static void                    DumpRuleAnalysis(void *,struct lhsParseNode *);
#endif
#endif

/****************************************************/
/* ParseDefrule: Coordinates all actions necessary  */
/*   for the parsing and creation of a defrule into */
/*   the current environment.                       */
/****************************************************/
globle int ParseDefrule(
  void *theEnv,
  char *readSource)
  {
#if (MAC_MCW || IBM_MCW) && (RUN_TIME || BLOAD_ONLY)
#pragma unused(theEnv,readSource)
#endif

#if (! RUN_TIME) && (! BLOAD_ONLY)
   SYMBOL_HN *ruleName;
   struct lhsParseNode *theLHS;
   struct expr *actions;
   struct token theToken;
   struct defrule *topDisjunct, *tempPtr;
   struct defruleModule *theModuleItem;
   int error;

   /*================================================*/
   /* Flush the buffer which stores the pretty print */
   /* representation for a rule.  Add the already    */
   /* parsed keyword defrule to this buffer.         */
   /*================================================*/

   SetPPBufferStatus(theEnv,ON);
   FlushPPBuffer(theEnv);
   SavePPBuffer(theEnv,"(defrule ");

   /*=========================================================*/
   /* Rules cannot be loaded when a binary load is in effect. */
   /*=========================================================*/

#if BLOAD || BLOAD_ONLY || BLOAD_AND_BSAVE
   if ((Bloaded(theEnv) == TRUE) && (! ConstructData(theEnv)->CheckSyntaxMode))
     {
      CannotLoadWithBloadMessage(theEnv,"defrule");
      return(TRUE);
     }
#endif

   /*================================================*/
   /* Parse the name and comment fields of the rule, */
   /* deleting the rule if it already exists.        */
   /*================================================*/

#if DEBUGGING_FUNCTIONS
   DefruleData(theEnv)->DeletedRuleDebugFlags = 0;
#endif

   ruleName = GetConstructNameAndComment(theEnv,readSource,&theToken,"defrule",
                                         EnvFindDefrule,EnvUndefrule,"*",FALSE,
                                         TRUE,TRUE);

   if (ruleName == NULL) return(TRUE);

   /*============================*/
   /* Parse the LHS of the rule. */
   /*============================*/

   theLHS = ParseRuleLHS(theEnv,readSource,&theToken,ValueToString(ruleName),&error);
   if (error)
     {
      ReturnPackedExpression(theEnv,PatternData(theEnv)->SalienceExpression);
      PatternData(theEnv)->SalienceExpression = NULL;
      return(TRUE);
     }

   /*============================*/
   /* Parse the RHS of the rule. */
   /*============================*/

   ClearParsedBindNames(theEnv);
   ExpressionData(theEnv)->ReturnContext = TRUE;
   actions = ParseRuleRHS(theEnv,readSource);

   if (actions == NULL)
     {
      ReturnPackedExpression(theEnv,PatternData(theEnv)->SalienceExpression);
      PatternData(theEnv)->SalienceExpression = NULL;
      ReturnLHSParseNodes(theEnv,theLHS);
      return(TRUE);
     }

   /*=======================*/
   /* Process the rule LHS. */
   /*=======================*/

   topDisjunct = ProcessRuleLHS(theEnv,theLHS,actions,ruleName,&error);

   ReturnExpression(theEnv,actions);
   ClearParsedBindNames(theEnv);
   ReturnLHSParseNodes(theEnv,theLHS);

   if (error)
     {
      ReturnPackedExpression(theEnv,PatternData(theEnv)->SalienceExpression);
      PatternData(theEnv)->SalienceExpression = NULL;
      return(TRUE);
     }

   /*==============================================*/
   /* If we're only checking syntax, don't add the */
   /* successfully parsed defrule to the KB.       */
   /*==============================================*/

   if (ConstructData(theEnv)->CheckSyntaxMode)
     {
      ReturnPackedExpression(theEnv,PatternData(theEnv)->SalienceExpression);
      PatternData(theEnv)->SalienceExpression = NULL;
      return(FALSE);
     }

   PatternData(theEnv)->SalienceExpression = NULL;

   /*======================================*/
   /* Save the nice printout of the rules. */
   /*======================================*/

   SavePPBuffer(theEnv,"\n");
   if (EnvGetConserveMemory(theEnv) == TRUE)
     { topDisjunct->header.ppForm = NULL; }
   else
     { topDisjunct->header.ppForm = CopyPPBuffer(theEnv); }

   /*=======================================*/
   /* Store a pointer to the rule's module. */
   /*=======================================*/

   theModuleItem = (struct defruleModule *)
                   GetModuleItem(theEnv,NULL,FindModuleItem(theEnv,"defrule")->moduleIndex);

   for (tempPtr = topDisjunct; tempPtr != NULL; tempPtr = tempPtr->disjunct)
     { tempPtr->header.whichModule = (struct defmoduleItemHeader *) theModuleItem; }

   /*===============================================*/
   /* Rule completely parsed. Add to list of rules. */
   /*===============================================*/

   AddToDefruleList(topDisjunct);

   /*========================================================================*/
   /* If a rule is redefined, then we want to restore its breakpoint status. */
   /*========================================================================*/

#if DEBUGGING_FUNCTIONS
   if (BitwiseTest(DefruleData(theEnv)->DeletedRuleDebugFlags,0))
     { EnvSetBreak(theEnv,topDisjunct); }
   if (BitwiseTest(DefruleData(theEnv)->DeletedRuleDebugFlags,1) || EnvGetWatchItem(theEnv,"activations"))
     { EnvSetDefruleWatchActivations(theEnv,ON,(void *) topDisjunct); }
   if (BitwiseTest(DefruleData(theEnv)->DeletedRuleDebugFlags,2) || EnvGetWatchItem(theEnv,"rules"))
     { EnvSetDefruleWatchFirings(theEnv,ON,(void *) topDisjunct); }
#endif

   /*================================*/
   /* Perform the incremental reset. */
   /*================================*/

   IncrementalReset(theEnv,topDisjunct);

   /*=============================================*/
   /* Return FALSE to indicate no errors occured. */
   /*=============================================*/

#endif
   return(FALSE);
  }

#if (! RUN_TIME) && (! BLOAD_ONLY)

/**************************************************************/
/* ProcessRuleLHS: Processes each of the disjuncts of a rule. */
/**************************************************************/
static struct defrule *ProcessRuleLHS(
  void *theEnv,
  struct lhsParseNode *theLHS,
  struct expr *actions,
  SYMBOL_HN *ruleName,
  int *error)
  {
   struct lhsParseNode *tempNode = NULL;
   struct defrule *topDisjunct = NULL, *currentDisjunct, *lastDisjunct = NULL;
   struct expr *newActions, *packPtr;
   int logicalJoin;
   int localVarCnt;
   int complexity;
   struct joinNode *lastJoin;
   intBool emptyLHS;

   /*================================================*/
   /* Initially set the parsing error flag to FALSE. */
   /*================================================*/

   *error = FALSE;

   /*===========================================================*/
   /* The top level of the construct representing the LHS of a  */
   /* rule is assumed to be an OR.  If the implied OR is at the */
   /* top level of the pattern construct, then remove it.       */
   /*===========================================================*/

   if (theLHS == NULL)
     { emptyLHS = TRUE; }
   else
     {
      emptyLHS = FALSE;
      if (theLHS->type == OR_CE) theLHS = theLHS->right;
     }
 
   /*=========================================*/
   /* Loop through each disjunct of the rule. */
   /*=========================================*/

   localVarCnt = CountParsedBindNames(theEnv);
   
   while ((theLHS != NULL) || (emptyLHS == TRUE))
     {
      /*===================================*/
      /* Analyze the LHS of this disjunct. */
      /*===================================*/

      if (emptyLHS)
        { tempNode = NULL; }
      else
        {
         if (theLHS->type == AND_CE) tempNode = theLHS->right;
         else if (theLHS->type == PATTERN_CE) tempNode = theLHS;
        }

      if (VariableAnalysis(theEnv,tempNode))
        {
         *error = TRUE;
         ReturnDefrule(theEnv,topDisjunct);
         return(NULL);
        }

      /*=========================================*/
      /* Perform entity dependent post analysis. */
      /*=========================================*/

      if (PostPatternAnalysis(theEnv,tempNode))
        {
         *error = TRUE;
         ReturnDefrule(theEnv,topDisjunct);
         return(NULL);
        }

      /*========================================================*/
      /* Print out developer information if it's being watched. */