globle CLIPS_BOOLEAN AddLogicalDependencies(
void *theEnv,
struct patternEntity *theEntity,
int existingEntity)
{
struct partialMatch *theBinds;
struct dependency *newDependency;
/*==============================================*/
/* If the rule has no logical patterns, then no */
/* dependencies have to be established. */
/*==============================================*/
if (EngineData(theEnv)->TheLogicalJoin == NULL)
{
if (existingEntity) RemoveEntityDependencies(theEnv,theEntity);
return(TRUE);
}
else if (existingEntity && (theEntity->dependents == NULL))
{ return(TRUE); }
/*============================================================*/
/* Find the partial match in the logical join associated with */
/* activation partial match. If the partial match cannot be */
/* found, then the partial match must have been deleted by a */
/* previous RHS action and the dependency link should not be */
/* added. */
/*============================================================*/
theBinds = FindLogicalBind(EngineData(theEnv)->TheLogicalJoin,EngineData(theEnv)->GlobalLHSBinds);
if (theBinds == NULL) return(FALSE);
/*==============================================================*/
/* Add a dependency link between the partial match and the data */
/* entity. The dependency links are stored in the partial match */
/* behind the data entities stored in the partial match and the */
/* activation link, if any. */
/*==============================================================*/
newDependency = get_struct(theEnv,dependency);
newDependency->dPtr = (void *) theEntity;
newDependency->next = (struct dependency *)
theBinds->binds[theBinds->bcount + theBinds->activationf].gm.theValue;
theBinds->binds[theBinds->bcount + theBinds->activationf].gm.theValue = (void *) newDependency;
/*================================================================*/
/* Add a dependency link between the entity and the partialMatch. */
/*================================================================*/
newDependency = get_struct(theEnv,dependency);
newDependency->dPtr = (void *) theBinds;
newDependency->next = (struct dependency *) theEntity->dependents;
theEntity->dependents = (void *) newDependency;
/*==================================================================*/
/* Return TRUE to indicate that the data entity should be asserted. */
/*==================================================================*/
return(TRUE);
}
bool AddLogicalDependencies(
Environment *theEnv,
struct patternEntity *theEntity,
bool existingEntity)
{
struct partialMatch *theBinds;
struct dependency *newDependency;
/*==============================================*/
/* If the rule has no logical patterns, then no */
/* dependencies have to be established. */
/*==============================================*/
if (EngineData(theEnv)->TheLogicalJoin == NULL)
{
if (existingEntity) RemoveEntityDependencies(theEnv,theEntity);
return true;
}
else if (existingEntity && (theEntity->dependents == NULL))
{ return true; }
/*===========================================================*/
/* Retrieve the partial match in the logical join associated */
/* with activation partial match (retrieved when the run */
/* command was initiated). If the partial match's parent */
/* links have been removed, then the partial match must have */
/* been deleted by a previous RHS action and the dependency */
/* link should not be added. */
/*===========================================================*/
theBinds = EngineData(theEnv)->TheLogicalBind;
if (theBinds == NULL) return false;
if ((theBinds->leftParent == NULL) && (theBinds->rightParent == NULL))
{ return false; }
/*==============================================================*/
/* Add a dependency link between the partial match and the data */
/* entity. The dependency links are stored in the partial match */
/* behind the data entities stored in the partial match and the */
/* activation link, if any. */
/*==============================================================*/
newDependency = get_struct(theEnv,dependency);
newDependency->dPtr = theEntity;
newDependency->next = (struct dependency *) theBinds->dependents;
theBinds->dependents = newDependency;
/*================================================================*/
/* Add a dependency link between the entity and the partialMatch. */
/*================================================================*/
newDependency = get_struct(theEnv,dependency);
newDependency->dPtr = theBinds;
newDependency->next = (struct dependency *) theEntity->dependents;
theEntity->dependents = newDependency;
/*==================================================================*/
/* Return true to indicate that the data entity should be asserted. */
/*==================================================================*/
return true;
}
globle BOOLEAN Retract(
void *vTheFact)
{
struct fact *theFact = (struct fact *) vTheFact;
/*===========================================*/
/* A fact can not be retracted while another */
/* fact is being asserted or retracted. */
/*===========================================*/
if (JoinOperationInProgress)
{
PrintErrorID("FACTMNGR",1,TRUE);
PrintRouter(WERROR,"Facts may not be retracted during pattern-matching\n");
return(FALSE);
}
/*====================================*/
/* A NULL fact pointer indicates that */
/* all facts should be retracted. */
/*====================================*/
if (theFact == NULL)
{
RemoveAllFacts();
return(TRUE);
}
/*======================================================*/
/* Check to see if the fact has already been retracted. */
/*======================================================*/
if (theFact->garbage) return(FALSE);
/*============================*/
/* Print retraction output if */
/* facts are being watched. */
/*============================*/
#if DEBUGGING_FUNCTIONS
if (theFact->whichDeftemplate->watch)
{
PrintRouter(WTRACE,"<== ");
PrintFactWithIdentifier(WTRACE,theFact);
PrintRouter(WTRACE,"\n");
}
#endif
/*==================================*/
/* Set the change flag to indicate */
/* the fact-list has been modified. */
/*==================================*/
ChangeToFactList = TRUE;
/*===============================================*/
/* Remove any links between the fact and partial */
/* matches in the join network. These links are */
/* used to keep track of logical dependencies. */
/*===============================================*/
#if LOGICAL_DEPENDENCIES
RemoveEntityDependencies((struct patternEntity *) theFact);
#endif
/*===========================================*/
/* Remove the fact from the fact hash table. */
/*===========================================*/
RemoveHashedFact(theFact);
/*=====================================*/
/* Remove the fact from the fact list. */
/*=====================================*/
if (theFact == LastFact)
{ LastFact = theFact->previousFact; }
if (theFact->previousFact == NULL)
{
FactList = FactList->nextFact;
if (FactList != NULL)
{ FactList->previousFact = NULL; }
}
else
{
theFact->previousFact->nextFact = theFact->nextFact;
if (theFact->nextFact != NULL)
{ theFact->nextFact->previousFact = theFact->previousFact; }
}
/*==================================*/
/* Update busy counts and ephemeral */
/* garbage information. */
/*==================================*/
FactDeinstall(theFact);
EphemeralItemCount++;
EphemeralItemSize += sizeof(struct fact) + (sizeof(struct field) * theFact->theProposition.multifieldLength);
/*========================================*/
/* Add the fact to the fact garbage list. */
/*========================================*/
theFact->nextFact = GarbageFacts;
GarbageFacts = theFact;
theFact->garbage = TRUE;
/*===================================================*/
/* Reset the evaluation error flag since expressions */
/* will be evaluated as part of the retract. */
/*===================================================*/
SetEvaluationError(FALSE);
/*===========================================*/
/* Loop through the list of all the patterns */
/* that matched the fact and process the */
/* retract operation for each one. */
/*===========================================*/
JoinOperationInProgress = TRUE;
NetworkRetract((struct patternMatch *) theFact->list);
JoinOperationInProgress = FALSE;
/*=========================================*/
/* Free partial matches that were released */
/* by the retraction of the fact. */
/*=========================================*/
if (ExecutingRule == NULL)
{ FlushGarbagePartialMatches(); }
/*=========================================*/
/* Retract other facts that were logically */
/* dependent on the fact just retracted. */
/*=========================================*/
#if LOGICAL_DEPENDENCIES
ForceLogicalRetractions();
#endif
/*===========================================*/
/* Force periodic cleanup if the retract was */
/* executed from an embedded application. */
/*===========================================*/
if ((CurrentEvaluationDepth == 0) && (! EvaluatingTopLevelCommand) &&
(CurrentExpression == NULL))
{ PeriodicCleanup(TRUE,FALSE); }
/*==================================*/
/* Return TRUE to indicate the fact */
/* was successfully retracted. */
/*==================================*/
return(TRUE);
}