factcom.c

NASA 开发使用的一个专家系统

   /*******************************************************/
   /*      "C" Language Integrated Production System      */
   /*                                                     */
   /*             CLIPS Version 6.05  04/09/97            */
   /*                                                     */
   /*                FACT COMMANDS MODULE                 */
   /*******************************************************/

/*************************************************************/
/* Purpose: Provides the facts, assert, retract, save-facts, */
/*   load-facts, set-fact-duplication, get-fact-duplication, */
/*   assert-string, and fact-index commands and functions.   */
/*                                                           */
/* Principal Programmer(s):                                  */
/*      Gary D. Riley                                        */
/*                                                           */
/* Contributing Programmer(s):                               */
/*      Brian L. Donnell                                     */
/*                                                           */
/* Revision History:                                         */
/*                                                           */
/*************************************************************/

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

#include "setup.h"

#if DEFTEMPLATE_CONSTRUCT

#define _FACTCOM_SOURCE_

#include "clipsmem.h"
#include "exprnpsr.h"
#include "factmngr.h"
#include "argacces.h"
#include "match.h"
#include "router.h"
#include "scanner.h"
#include "constant.h"
#include "factrhs.h"
#include "factmch.h"
#include "extnfunc.h"
#include "tmpltpsr.h"
#include "tmpltutl.h"
#include "facthsh.h"
#include "modulutl.h"
#include "strngrtr.h"
#include "tmpltdef.h"
#include "tmpltfun.h"

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

#include "factcom.h"

#define INVALID     -2L
#define UNSPECIFIED -1L

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

#if ANSI_COMPILER
#if (! RUN_TIME)
   static struct expr            *AssertParse(struct expr *,char *);
#endif
#if DEBUGGING_FUNCTIONS
   static long int                GetFactsArgument(int,int);
#endif
   static struct expr            *StandardLoadFact(char *,struct token *);
   static DATA_OBJECT_PTR         GetSaveFactsDeftemplateNames(struct expr *,int,int *,int *);
#else
#if (! RUN_TIME)
   static struct expr            *AssertParse();
#endif
#if DEBUGGING_FUNCTIONS
   static long int                GetFactsArgument();
#endif
   static struct expr            *StandardLoadFact();
   static DATA_OBJECT_PTR         GetSaveFactsDeftemplateNames();
#endif

/***************************************/
/* FactCommandDefinitions: Initializes */
/*   fact commands and functions.      */
/***************************************/
globle VOID FactCommandDefinitions()
  {
#if ! RUN_TIME
#if DEBUGGING_FUNCTIONS
   DefineFunction2("facts", 'v', PTIF FactsCommand,        "FactsCommand", "*4iu");
#endif

   DefineFunction("assert", 'u', PTIF AssertCommand,  "AssertCommand");
   DefineFunction2("retract", 'v', PTIF RetractCommand, "RetractCommand","1*z");
   DefineFunction2("assert-string", 'u', PTIF AssertStringFunction,   "AssertStringFunction", "11s");
   DefineFunction2("str-assert", 'u', PTIF AssertStringFunction,   "AssertStringFunction", "11s");

   DefineFunction2("get-fact-duplication",'b',
                   GetFactDuplicationCommand,"GetFactDuplicationCommand", "00");
   DefineFunction2("set-fact-duplication",'b',
                   SetFactDuplicationCommand,"SetFactDuplicationCommand", "11");

   DefineFunction2("save-facts", 'b', PTIF SaveFactsCommand, "SaveFactsCommand", "1*wk");
   DefineFunction2("load-facts", 'b', PTIF LoadFactsCommand, "LoadFactsCommand", "11k");
   DefineFunction2("fact-index", 'l', PTIF FactIndexFunction,"FactIndexFunction", "11y");
#endif

#if (! RUN_TIME)
   AddFunctionParser("assert",AssertParse);
   FuncSeqOvlFlags("assert",CLIPS_FALSE,CLIPS_FALSE);
#endif
  }

/***************************************/
/* AssertCommand: CLIPS access routine */
/*   for the assert function.          */
/***************************************/
globle VOID AssertCommand(rv)
  DATA_OBJECT_PTR rv;
  {
   struct deftemplate *theDeftemplate;
   struct field *theField;
   DATA_OBJECT theValue;
   struct expr *theExpression;
   struct templateSlot *slotPtr;
   struct fact *newFact;
   int error = CLIPS_FALSE;
   int i;
   struct fact *theFact;

   /*===================================================*/
   /* Set the default return value to the symbol FALSE. */
   /*===================================================*/

   SetpType(rv,SYMBOL);
   SetpValue(rv,CLIPSFalseSymbol);

   /*================================*/
   /* Get the deftemplate associated */
   /* with the fact being asserted.  */
   /*================================*/

   theExpression = GetFirstArgument();
   theDeftemplate = (struct deftemplate *) theExpression->value;
      
   /*=======================================*/
   /* Create the fact and store the name of */
   /* the deftemplate as the 1st field.     */
   /*=======================================*/
   
   if (theDeftemplate->implied == CLIPS_FALSE) 
     { 
      newFact = CreateFactBySize((int) theDeftemplate->numberOfSlots);
      slotPtr = theDeftemplate->slotList;
     }
   else 
     {
      newFact = CreateFactBySize(1);
      if (theExpression->nextArg == NULL)  
        { 
         newFact->theProposition.theFields[0].type = MULTIFIELD;
         newFact->theProposition.theFields[0].value = CreateMultifield2(0L);
        }
      slotPtr = NULL;
     }
   
   newFact->whichDeftemplate = theDeftemplate;
   
   /*===================================================*/
   /* Evaluate the expression associated with each slot */
   /* and store the result in the appropriate slot of   */
   /* the newly created fact.                           */
   /*===================================================*/
   
   theField = newFact->theProposition.theFields;
   
   for (theExpression = theExpression->nextArg, i = 0;
        theExpression != NULL;
        theExpression = theExpression->nextArg, i++)
     {
      /*===================================================*/
      /* Evaluate the expression to be stored in the slot. */
      /*===================================================*/
      
      EvaluateExpression(theExpression,&theValue);   
      
      /*============================================================*/
      /* A multifield value can't be stored in a single field slot. */
      /*============================================================*/
      
      if ((slotPtr != NULL) ?
          (slotPtr->multislot == CLIPS_FALSE) && (theValue.type == MULTIFIELD) :
          CLIPS_FALSE)
        {
         MultiIntoSingleFieldSlotError(slotPtr,theDeftemplate);
         theValue.type = SYMBOL;
         theValue.value = CLIPSFalseSymbol;
         error = CLIPS_TRUE;
        }
        
      /*==============================*/
      /* Store the value in the slot. */
      /*==============================*/
      
      theField[i].type = (short) theValue.type;
      theField[i].value = theValue.value;
      
      /*========================================*/
      /* Get the information for the next slot. */
      /*========================================*/
      
      if (slotPtr != NULL) slotPtr = slotPtr->next;
     }

   /*============================================*/
   /* If an error occured while generating the   */
   /* fact's slot values, then abort the assert. */
   /*============================================*/
            
   if (error) 
     {
      ReturnFact(newFact);
      return;
     }
     
   /*================================*/
   /* Add the fact to the fact-list. */
   /*================================*/

   theFact = (struct fact *) Assert((VOID *) newFact);

   /*========================================*/
   /* The asserted fact is the return value. */
   /*========================================*/

   if (theFact != NULL)
     {
      SetpType(rv,FACT_ADDRESS);
      SetpValue(rv,(VOID *) theFact);
     }
     
   return;
  }
  
/****************************************/
/* RetractCommand: CLIPS access routine */
/*   for the retract command.           */
/****************************************/
globle VOID RetractCommand()
  {
   long int factIndex;
   struct fact *ptr;
   struct expr *theArgument;
   DATA_OBJECT theResult;
   int argNumber;

   /*================================*/
   /* Iterate through each argument. */
   /*================================*/
   
   for (theArgument = GetFirstArgument(), argNumber = 1;
        theArgument != NULL;
        theArgument = GetNextArgument(theArgument), argNumber++)
     {
      /*========================*/
      /* Evaluate the argument. */
      /*========================*/
      
      EvaluateExpression(theArgument,&theResult);
      
      /*===============================================*/
      /* If the argument evaluates to an integer, then */
      /* it's assumed to be the fact index of the fact */
      /* to be retracted.                              */
      /*===============================================*/
      
      if (theResult.type == INTEGER)
        {
         /*==========================================*/
         /* A fact index must be a positive integer. */
         /*==========================================*/
         
         factIndex = ValueToLong(theResult.value);
         if (factIndex < 0)
           {            
            ExpectedTypeError1("retract",argNumber,"fact-address, fact-index, or the symbol *");
            return;
           }
         
         /*================================================*/
         /* See if a fact with the specified index exists. */
         /*================================================*/
         
         ptr = FindIndexedFact(factIndex);
         
         /*=====================================*/
         /* If the fact exists then retract it, */
         /* otherwise print an error message.   */
         /*=====================================*/
         
         if (ptr != NULL)
           { Retract((VOID *) ptr); }
         else
           {
            char tempBuffer[20];
            sprintf(tempBuffer,"f-%ld",factIndex);
            CantFindItemErrorMessage("fact",tempBuffer);
           }
        }
        
      /*===============================================*/
      /* Otherwise if the argument evaluates to a fact */
      /* address, we can directly retract it.          */
      /*===============================================*/
      
      else if (theResult.type == FACT_ADDRESS)
        { Retract(theResult.value); }
        
      /*============================================*/
      /* Otherwise if the argument evaluates to the */
      /* symbol *, then all facts are retracted.    */
      /*============================================*/
      
      else if ((theResult.type == SYMBOL) ?
               (strcmp(ValueToString(theResult.value),"*") == 0) : CLIPS_FALSE)
        {
         RemoveAllFacts();
         return;
        }
        
      /*============================================*/
      /* Otherwise the argument has evaluated to an */
      /* illegal value for the retract command.     */
      /*============================================*/
      
      else
        {
         ExpectedTypeError1("retract",argNumber,"fact-address, fact-index, or the symbol *");
         SetEvaluationError(TRUE);
        }
     }
  }

/***************************************************/
/* SetFactDuplicationCommand: CLIPS access routine */
/*   for the set-fact-duplication command.         */
/***************************************************/
globle int SetFactDuplicationCommand()
  {
   int oldValue;
   DATA_OBJECT theValue;

   /*=====================================================*/
   /* Get the old value of the fact duplication behavior. */
   /*=====================================================*/
   
   oldValue = GetFactDuplication();

   /*============================================*/
   /* Check for the correct number of arguments. */
   /*============================================*/
   
   if (ArgCountCheck("set-fact-duplication",EXACTLY,1) == -1)
     { return(oldValue); }

   /*========================*/
   /* Evaluate the argument. */
   /*========================*/
   
   RtnUnknown(1,&theValue);

   /*===============================================================*/
   /* If the argument evaluated to FALSE, then the fact duplication */
   /* behavior is disabled, otherwise it is enabled.                */
   /*===============================================================*/
   
   if ((theValue.value == CLIPSFalseSymbol) && (theValue.type == SYMBOL))
     { SetFactDuplication(CLIPS_FALSE); }
   else
     { SetFactDuplication(CLIPS_TRUE); }

   /*========================================================*/
   /* Return the old value of the fact duplication behavior. */
   /*========================================================*/
   
   return(oldValue);
  }

/***************************************************/
/* GetFactDuplicationCommand: CLIPS access routine */
/*   for the get-fact-duplication command.         */
/***************************************************/
globle int GetFactDuplicationCommand()
  {
   int currentValue;

   /*=========================================================*/
   /* Get the current value of the fact duplication behavior. */
   /*=========================================================*/
   
   currentValue = GetFactDuplication();

   /*============================================*/
   /* Check for the correct number of arguments. */
   /*============================================*/   

   if (ArgCountCheck("get-fact-duplication",EXACTLY,0) == -1)
     { return(currentValue); }
     
   /*============================================================*/
   /* Return the current value of the fact duplication behavior. */
   /*============================================================*/

   return(currentValue);
  }

/*******************************************/
/* FactIndexFunction: CLIPS access routine */
/*   for the fact-index function.          */
/*******************************************/
globle long int FactIndexFunction()
  {
   DATA_OBJECT item;