tmpltrhs.c

clips源代码

      if (newField == NULL)
       {
        *error = TRUE;
        SingleFieldSlotCardinalityError(theEnv,slotPtr->slotName->contents);
        return(NULL);
       }

      /*==============================================*/
      /* A function returning a multifield value can  */
      /* not be called to get the value for the slot. */
      /*==============================================*/

      if ((newField->type == FCALL) ? (ExpressionFunctionType(newField) == 'm') :
                                      (newField->type == MF_VARIABLE))
       {
        *error = TRUE;
        SingleFieldSlotCardinalityError(theEnv,slotPtr->slotName->contents);
        ReturnExpression(theEnv,newField);
        return(NULL);
       }

      /*============================*/
      /* Move on to the next token. */
      /*============================*/

      GetToken(theEnv,inputSource,tempToken);
     }

   /*========================================*/
   /* Handle a multifield slot. Build a list */
   /* of the values stored in the slot.      */
   /*========================================*/

   else
     {
      SavePPBuffer(theEnv," ");
      valueList = GetAssertArgument(theEnv,inputSource,tempToken,
                                     error,RPAREN,constantsOnly,&printError);
      if (*error)
        {
         if (printError) SyntaxErrorMessage(theEnv,"deftemplate pattern");
         return(NULL);
        }

      if (valueList == NULL)
        {
         PPBackup(theEnv);
         PPBackup(theEnv);
         SavePPBuffer(theEnv,")");
        }

      lastValue = valueList;

      while (lastValue != NULL) /* (tempToken->type != RPAREN) */
        {
         if (tempToken->type == RPAREN)
           { SavePPBuffer(theEnv," "); }
         else
           {
            /* PPBackup(theEnv); */
            SavePPBuffer(theEnv," ");
            /* SavePPBuffer(theEnv,tempToken->printForm); */
           }

         newField = GetAssertArgument(theEnv,inputSource,tempToken,error,RPAREN,constantsOnly,&printError);
         if (*error)
           {
            if (printError) SyntaxErrorMessage(theEnv,"deftemplate pattern");
            ReturnExpression(theEnv,valueList);
            return(NULL);
           }

         if (newField == NULL)
           {
            PPBackup(theEnv);
            PPBackup(theEnv);
            SavePPBuffer(theEnv,")");
           }

         lastValue->nextArg = newField;
         lastValue = newField;
        }

      newField = valueList;
     }

   /*==========================================================*/
   /* Slot definition must be closed with a right parenthesis. */
   /*==========================================================*/

   if (tempToken->type != RPAREN)
     {
      SingleFieldSlotCardinalityError(theEnv,slotPtr->slotName->contents);
      *error = TRUE;
      ReturnExpression(theEnv,newField);
      return(NULL);
     }

   /*=========================================================*/
   /* Build and return a structure describing the slot value. */
   /*=========================================================*/

   nextSlot = GenConstant(theEnv,SYMBOL,slotPtr->slotName);
   nextSlot->argList = newField;

   return(nextSlot);
  }

/*************************************************************************/
/* ReorderAssertSlotValues: Rearranges the asserted values to correspond */
/*   to the order of the values described by the deftemplate.            */
/*************************************************************************/
static struct expr *ReorderAssertSlotValues(
  void *theEnv,
  struct templateSlot *slotPtr,
  struct expr *firstSlot,
  int *error)
  {
   struct expr *firstArg = NULL;
   struct expr *lastArg = NULL, *newArg;

   /*=============================================*/
   /* Loop through each of the slots in the order */
   /* they're found in the deftemplate.           */
   /*=============================================*/

   for (;
        slotPtr != NULL;
        slotPtr = slotPtr->next)
     {
      /*==============================================*/
      /* Get either the value specified in the assert */
      /* command or the default value for the slot.   */
      /*==============================================*/

      newArg = GetSlotAssertValues(theEnv,slotPtr,firstSlot,error);

      if (*error)
        {
         ReturnExpression(theEnv,firstArg);
         return(NULL);
        }

      /*=====================================*/
      /* Add the value to the list of values */
      /* for the assert command.             */
      /*=====================================*/

      if (newArg != NULL)
        {
         if (lastArg == NULL)
           { firstArg = newArg; }
         else
           { lastArg->nextArg = newArg; }

         lastArg = newArg;
        }
     }

   /*==============================*/
   /* Return the list of arguments */
   /* for the assert command.      */
   /*==============================*/

   return(firstArg);
  }

/***************************************************************/
/* GetSlotAssertValues: Gets the assert value for a given slot */
/*   of a deftemplate. If the value was supplied by the user,  */
/*   it will be used. If not the default value or default      */
/*   default value will be used.                               */
/***************************************************************/
static struct expr *GetSlotAssertValues(
  void *theEnv,
  struct templateSlot *slotPtr,
  struct expr *firstSlot,
  int *error)
  {
   struct expr *slotItem;
   struct expr *newArg, *tempArg;
   DATA_OBJECT theDefault;

   /*==================================================*/
   /* Determine if the slot is assigned in the assert. */
   /*==================================================*/

   slotItem = FindAssertSlotItem(slotPtr,firstSlot);

   /*==========================================*/
   /* If the slot is assigned, use that value. */
   /*==========================================*/

   if (slotItem != NULL)
     {
      newArg = slotItem->argList;
      slotItem->argList = NULL;
     }

   /*=================================*/
   /* Otherwise, use a default value. */
   /*=================================*/

   else
     {
      /*================================================*/
      /* If the (default ?NONE) attribute was specified */
      /* for the slot, then a value must be supplied.   */
      /*================================================*/

      if (slotPtr->noDefault)
        {
         PrintErrorID(theEnv,"TMPLTRHS",1,TRUE);
         EnvPrintRouter(theEnv,WERROR,"Slot ");
         EnvPrintRouter(theEnv,WERROR,slotPtr->slotName->contents);
         EnvPrintRouter(theEnv,WERROR," requires a value because of its (default ?NONE) attribute.\n");
         *error = TRUE;
         return(NULL);
        }

      /*===================================================*/
      /* If the (default ?DERIVE) attribute was specified  */
      /* (the default), then derive the default value from */
      /* the slot's constraints.                           */
      /*===================================================*/

      else if ((slotPtr->defaultPresent == FALSE) &&
               (slotPtr->defaultDynamic == FALSE))
        {
         DeriveDefaultFromConstraints(theEnv,slotPtr->constraints,&theDefault,
                                      (int) slotPtr->multislot,TRUE);
         newArg = ConvertValueToExpression(theEnv,&theDefault);
        }

      /*=========================================*/
      /* Otherwise, use the expression contained */
      /* in the default attribute.               */
      /*=========================================*/

      else
        { newArg = CopyExpression(theEnv,slotPtr->defaultList); }
     }

   /*=======================================================*/
   /* Since a multifield slot default can contain a list of */
   /* values, the values need to have a store-multifield    */
   /* function called wrapped around it to group all of the */
   /* values into a single multifield value.                */
   /*=======================================================*/

   if (slotPtr->multislot)
     {
      tempArg = GenConstant(theEnv,FACT_STORE_MULTIFIELD,AddBitMap(theEnv,(void *) "\0",1));
      tempArg->argList = newArg;
      newArg = tempArg;
     }

   /*==============================================*/
   /* Return the value to be asserted in the slot. */
   /*==============================================*/

   return(newArg);
  }

/*******************************************************************/
/* FindAssertSlotItem: Finds a particular slot in a list of slots. */
/*******************************************************************/
static struct expr *FindAssertSlotItem(
  struct templateSlot *slotPtr,
  struct expr *listOfSlots)
  {
   while (listOfSlots != NULL)
     {
      if (listOfSlots->value == (void *) slotPtr->slotName) return (listOfSlots);
      listOfSlots = listOfSlots->nextArg;
     }

   return(NULL);
  }

#endif /* DEFTEMPLATE_CONSTRUCT */