factfun.c

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

/*************************************************************/
/* Purpose:                                                  */
/*                                                           */
/*                                                           */
/* (fact-existp <fact-address-or-index>)                     */
/*    Returns TRUE if the fact exists, otherwise FALSE is    */
/*    returned.                                              */
/*                                                           */
/* (fact-relation <fact-address-or-index>)                   */
/*    Returns the deftemplate name of the fact. Returns      */
/*    False if the specified fact doesn't exist.             */
/*                                                           */
/* (fact-slot-value <fact-address-or-index> <slot-name>)     */
/*    Returns the contents of a slot (use the slot name      */
/*    implied for the implied multifield slot of an ordered  */
/*    fact). Returns the value FALSE if the slot name is     */
/*    invalid or the fact doesn't exist.                     */
/*                                                           */
/* (fact-slot-names <fact-address-or-index>)                 */
/*    Returns the slot names associated with a fact in a     */
/*    multifield value. Returns FALSE if the fact doesn't    */
/*    exist.                                                 */
/*                                                           */
/* (get-fact-list [<module-name>])                           */
/*    Returns the list of facts visible to the specified     */
/*    module or to the current module if none is specified.  */
/*    If * is specified then all facts are returned.         */
/*                                                           */
/* Principal Programmer(s):                                  */
/*      Gary D. Riley                                        */
/*                                                           */
/* Contributing Programmer(s):                               */
/*                                                           */
/* Revision History:                                         */
/*                                                           */
/*************************************************************/

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

#include "setup.h"

#if DEFTEMPLATE_CONSTRUCT

#define _FACTFUN_SOURCE_

#include "extnfunc.h"
#include "argacces.h"
#include "prntutil.h"
#include "tmpltutl.h"

#include "factfun.h"

/****************************************************/
/* FactFunctionDefinitions: Defines fact functions. */
/****************************************************/
globle VOID FactFunctionDefinitions()
  {   
#if ! RUN_TIME
   DefineFunction2("fact-existp",  'b', PTIF FactExistpFunction,  "FactExistpFunction", "11z");
   DefineFunction2("fact-relation",'w', PTIF FactRelationFunction,"FactRelationFunction", "11z");
   DefineFunction2("fact-slot-value",'u', PTIF FactSlotValueFunction,"FactSlotValueFunction", "22*zw");
   DefineFunction2("fact-slot-names",'u', PTIF FactSlotNamesFunction,"FactSlotNamesFunction", "11z");
   DefineFunction2("get-fact-list",'m',PTIF GetFactListFunction,"GetFactListFunction","01w");
#endif
  }

/**********************************************/
/* FactRelationFunction: CLIPS access routine */
/*   for the fact-relation function.          */
/**********************************************/
globle VOID *FactRelationFunction()
  {
   struct fact *theFact;

   if (ArgCountCheck("fact-relation",EXACTLY,1) == -1) return(CLIPSFalseSymbol);

   theFact = GetFactAddressOrIndexArgument("fact-relation",1,CLIPS_FALSE);
   
   if (theFact == NULL) return(CLIPSFalseSymbol);
   
   return(FactRelation(theFact));
  }

/**************************************/
/* FactRelation: C access routine for */
/*   the fact-relation function.      */
/**************************************/
globle VOID *FactRelation(vTheFact)
  VOID *vTheFact;
  {
   struct fact *theFact = (struct fact *) vTheFact;
   
   return((VOID *) theFact->whichDeftemplate->header.name);
  }
  
/********************************************/
/* FactExistpFunction: CLIPS access routine */
/*   for the fact-existp function.          */
/********************************************/
globle long int FactExistpFunction()
  {
   struct fact *theFact;

   if (ArgCountCheck("fact-existp",EXACTLY,1) == -1) return(-1L);

   theFact = GetFactAddressOrIndexArgument("fact-existp",1,CLIPS_FALSE);
   
   return(FactExistp(theFact));
  }

/************************************/
/* FactExistp: C access routine for */
/*   the fact-existp function.      */
/************************************/
globle long int FactExistp(vTheFact)
  VOID *vTheFact;
  {
   struct fact *theFact = (struct fact *) vTheFact;
   
   if (theFact == NULL) return(CLIPS_FALSE);
   
   if (theFact->garbage) return(CLIPS_FALSE);
   
   return(CLIPS_TRUE);
  }
  
/***********************************************/
/* FactSlotValueFunction: CLIPS access routine */
/*   for the fact-slot-value function.         */
/***********************************************/
globle VOID FactSlotValueFunction(returnValue)
  DATA_OBJECT *returnValue;
  {
   struct fact *theFact;
   DATA_OBJECT theValue;
   
   /*=============================================*/
   /* Set up the default return value for errors. */
   /*=============================================*/
   
   returnValue->type = SYMBOL;
   returnValue->value = CLIPSFalseSymbol;
   
   /*============================================*/
   /* Check for the correct number of arguments. */
   /*============================================*/
   
   if (ArgCountCheck("fact-slot-value",EXACTLY,2) == -1) return;

   /*================================*/
   /* Get the reference to the fact. */
   /*================================*/
   
   theFact = GetFactAddressOrIndexArgument("fact-slot-value",1,CLIPS_TRUE);
   if (theFact == NULL) return;
   
   /*===========================*/
   /* Get the name of the slot. */
   /*===========================*/
   
   if (ArgTypeCheck("fact-slot-value",2,SYMBOL,&theValue) == CLIPS_FALSE) 
     { return; }

   /*=======================*/
   /* Get the slot's value. */
   /*=======================*/
   
   FactSlotValue(theFact,DOToString(theValue),returnValue);
  }

/***************************************/
/* FactSlotValue: C access routine for */
/*   the fact-slot-value function.     */
/***************************************/
globle VOID FactSlotValue(vTheFact,theSlotName,returnValue)
  VOID *vTheFact;
  char *theSlotName;
  DATA_OBJECT *returnValue;
  {
   struct fact *theFact = (struct fact *) vTheFact;
   int position;

   /*==================================================*/
   /* Make sure the slot exists (the symbol implied is */
   /* used for the implied slot of an ordered fact).   */
   /*==================================================*/
   
   if (theFact->whichDeftemplate->implied)
     {
      if (strcmp(theSlotName,"implied") != 0)
        {
         SetEvaluationError(CLIPS_TRUE);
         InvalidDeftemplateSlotMessage(theSlotName,
                                       ValueToString(theFact->whichDeftemplate->header.name));
         return;
        }
     }
   
   else if (FindSlot(theFact->whichDeftemplate,AddSymbol(theSlotName),&position) == NULL)
     {
      SetEvaluationError(CLIPS_TRUE);
      InvalidDeftemplateSlotMessage(theSlotName,
                                    ValueToString(theFact->whichDeftemplate->header.name));
      return;
     }
     
   /*==========================*/
   /* Return the slot's value. */
   /*==========================*/
   
   if (theFact->whichDeftemplate->implied)
     { GetFactSlot(theFact,NULL,returnValue); }
   else
     { GetFactSlot(theFact,theSlotName,returnValue); }
  }

/***********************************************/
/* FactSlotNamesFunction: CLIPS access routine */
/*   for the fact-slot-names function.         */
/***********************************************/
globle VOID FactSlotNamesFunction(returnValue)
  DATA_OBJECT *returnValue;
  {
   struct fact *theFact;

   /*=============================================*/
   /* Set up the default return value for errors. */
   /*=============================================*/
   
   returnValue->type = SYMBOL;
   returnValue->value = CLIPSFalseSymbol;
   
   /*============================================*/
   /* Check for the correct number of arguments. */
   /*============================================*/
   
   if (ArgCountCheck("fact-slot-names",EXACTLY,1) == -1) return;

   /*================================*/
   /* Get the reference to the fact. */
   /*================================*/

   theFact = GetFactAddressOrIndexArgument("fact-slot-names",1,CLIPS_TRUE);
   if (theFact == NULL) return;