tmpltpsr.c

NASA 开发使用的一个专家系统

  /*=======================*/
  /* Return the slot list. */
  /*=======================*/

  return(slotList);
 }

/*****************************************************/
/* ParseSlot: Parses a single slot of a deftemplate. */
/*****************************************************/
static struct templateSlot *ParseSlot(readSource,inputToken,slotList)
  char *readSource;
  struct token *inputToken;
  struct templateSlot *slotList;
  {
   int parsingMultislot;
   SYMBOL_HN *slotName;
   struct templateSlot *newSlot;
   int rv;

   /*=====================================================*/
   /* Slots must  begin with keyword field or multifield. */
   /*=====================================================*/

   if ((strcmp(ValueToString(inputToken->value),"field") != 0) &&
       (strcmp(ValueToString(inputToken->value),"multifield") != 0) &&
       (strcmp(ValueToString(inputToken->value),"slot") != 0) &&
       (strcmp(ValueToString(inputToken->value),"multislot") != 0))
     {
      SyntaxErrorMessage("deftemplate");
      DeftemplateError = CLIPS_TRUE;
      return(NULL);
     }

   /*===============================================*/
   /* Determine if multifield slot is being parsed. */
   /*===============================================*/

   if ((strcmp(ValueToString(inputToken->value),"multifield") == 0) ||
       (strcmp(ValueToString(inputToken->value),"multislot") == 0))
     { parsingMultislot = CLIPS_TRUE; }
   else
     { parsingMultislot = CLIPS_FALSE; }

   /*========================================*/
   /* The name of the slot must be a symbol. */
   /*========================================*/

   SavePPBuffer(" ");
   GetToken(readSource,inputToken);
   if (inputToken->type != SYMBOL)
     {
      SyntaxErrorMessage("deftemplate");
      DeftemplateError = CLIPS_TRUE;
      return(NULL);
     }

   slotName = (SYMBOL_HN *) inputToken->value;

   /*================================================*/
   /* Determine if the slot has already been parsed. */
   /*================================================*/
   
   while (slotList != NULL)
     {
      if (slotList->slotName == slotName)
        {
         AlreadyParsedErrorMessage("slot ",ValueToString(slotList->slotName));
         DeftemplateError = CLIPS_TRUE;
         return(NULL);
        }
        
      slotList = slotList->next;
     }
     
   /*===================================*/
   /* Parse the attributes of the slot. */
   /*===================================*/

   newSlot = DefinedSlots(readSource,slotName,parsingMultislot,inputToken);
   if (newSlot == NULL)
     {
      DeftemplateError = CLIPS_TRUE;
      return(NULL);
     }

   /*=================================*/
   /* Check for slot conflict errors. */
   /*=================================*/

   if (CheckConstraintParseConflicts(newSlot->constraints) == CLIPS_FALSE)
     {
      ReturnSlots(newSlot);
      DeftemplateError = CLIPS_TRUE;
      return(NULL);
     }
         
   if ((newSlot->defaultPresent) || (newSlot->defaultDynamic))
     { rv = ConstraintCheckExpressionChain(newSlot->defaultList,newSlot->constraints); }
   else
     { rv = NO_VIOLATION; }
     
   if ((rv != NO_VIOLATION) && GetStaticConstraintChecking())
     {
      char *temp;
      if (newSlot->defaultDynamic) temp = "the default-dynamic attribute";
      else temp = "the default attribute";
      ConstraintViolationErrorMessage("An expression",temp,CLIPS_FALSE,0,
                                      newSlot->slotName,0,rv,newSlot->constraints,CLIPS_TRUE);
      ReturnSlots(newSlot);
      DeftemplateError = CLIPS_TRUE;
      return(NULL);
     }

   /*==================*/
   /* Return the slot. */
   /*==================*/

   return(newSlot);
  }

/**************************************************************/
/* DefinedSlots: Parses a field or multifield slot attribute. */
/**************************************************************/
static struct templateSlot *DefinedSlots(readSource,slotName,multifieldSlot,inputToken)
  char *readSource;
  SYMBOL_HN *slotName;
  int multifieldSlot;
  struct token *inputToken;
  {
   struct templateSlot *newSlot;
   struct expr *defaultList;
   int defaultFound = CLIPS_FALSE;
   int noneSpecified, deriveSpecified;
   CONSTRAINT_PARSE_RECORD parsedConstraints;

   /*===========================*/
   /* Build the slot container. */
   /*===========================*/

   newSlot = get_struct(templateSlot);
   newSlot->slotName = slotName;
   newSlot->defaultList = NULL;
   newSlot->constraints = GetConstraintRecord();
   if (multifieldSlot)
     { newSlot->constraints->multifieldsAllowed = CLIPS_TRUE; }
   newSlot->multislot = multifieldSlot;
   newSlot->noDefault = CLIPS_FALSE;
   newSlot->defaultPresent = CLIPS_FALSE;
   newSlot->defaultDynamic = CLIPS_FALSE;
   newSlot->next = NULL;
   
   /*========================================*/
   /* Parse the primitive slot if it exists. */
   /*========================================*/

   InitializeConstraintParseRecord(&parsedConstraints);
   GetToken(readSource,inputToken);

   while (inputToken->type != RPAREN)
     {
      PPBackup();
      SavePPBuffer(" ");
      SavePPBuffer(inputToken->printForm);

      /*================================================*/
      /* Slot attributes begin with a left parenthesis. */
      /*================================================*/

      if (inputToken->type != LPAREN)
        {
         SyntaxErrorMessage("deftemplate");
         ReturnSlots(newSlot);
         DeftemplateError = CLIPS_TRUE;
         return(NULL);
        }

      /*=============================================*/
      /* The name of the attribute must be a symbol. */
      /*=============================================*/

      GetToken(readSource,inputToken);
      if (inputToken->type != SYMBOL)
        {
         SyntaxErrorMessage("deftemplate");
         ReturnSlots(newSlot);
         DeftemplateError = CLIPS_TRUE;
         return(NULL);
        }

      /*================================================================*/
      /* Determine if the attribute is one of the standard constraints. */
      /*================================================================*/

      if (StandardConstraint(ValueToString(inputToken->value)))
        {
         if (ParseStandardConstraint(readSource,(ValueToString(inputToken->value)),
                                     newSlot->constraints,&parsedConstraints,
                                     multifieldSlot) == CLIPS_FALSE)
           {
            DeftemplateError = CLIPS_TRUE;
            ReturnSlots(newSlot);
            return(NULL);
           }
        }

      /*=================================================*/
      /* else if the attribute is the default attribute, */
      /* then get the default list for this slot.        */
      /*=================================================*/

      else if ((strcmp(ValueToString(inputToken->value),"default") == 0) ||
               (strcmp(ValueToString(inputToken->value),"default-dynamic") == 0)) 
        {
         /*======================================================*/
         /* Check to see if the default has already been parsed. */
         /*======================================================*/
         
         if (defaultFound)
           {
            AlreadyParsedErrorMessage("default attribute",NULL);
            DeftemplateError = CLIPS_TRUE;
            ReturnSlots(newSlot);
            return(NULL);
           }
         
         newSlot->noDefault = CLIPS_FALSE;
           
         /*=====================================================*/
         /* Determine whether the default is dynamic or static. */
         /*=====================================================*/
         
         if (strcmp(ValueToString(inputToken->value),"default") == 0) 
           { 
            newSlot->defaultPresent = CLIPS_TRUE;
            newSlot->defaultDynamic = CLIPS_FALSE;
           }
         else 
           { 
            newSlot->defaultPresent = CLIPS_FALSE;
            newSlot->defaultDynamic = CLIPS_TRUE;
           }
         
         /*===================================*/
         /* Parse the list of default values. */
         /*===================================*/
         
         defaultList = ParseDefault(readSource,multifieldSlot,(int) newSlot->defaultDynamic,
                                  CLIPS_TRUE,&noneSpecified,&deriveSpecified,&DeftemplateError);
         if (DeftemplateError == CLIPS_TRUE)
           {
            ReturnSlots(newSlot);
            return(NULL);
           }
         
         /*==================================*/
         /* Store the default with the slot. */
         /*==================================*/
         
         defaultFound = CLIPS_TRUE;
         if (deriveSpecified) newSlot->defaultPresent = CLIPS_FALSE;
         else if (noneSpecified)
           {
            newSlot->noDefault = CLIPS_TRUE;
            newSlot->defaultPresent = CLIPS_FALSE;
           }
         newSlot->defaultList = defaultList;
        }

      /*============================================*/
      /* Otherwise the attribute is an invalid one. */
      /*============================================*/

      else
        {
         SyntaxErrorMessage("slot attributes");
         ReturnSlots(newSlot);
         DeftemplateError = CLIPS_TRUE;
         return(NULL);
        }

      /*===================================*/
      /* Begin parsing the next attribute. */
      /*===================================*/

      GetToken(readSource,inputToken);
     }

   /*============================*/
   /* Return the attribute list. */
   /*============================*/

   return(newSlot);
  }

#endif /* (! RUN_TIME) && (! BLOAD_ONLY) */

#endif /* DEFTEMPLATE_CONSTRUCT */