POINTER st_ExistGenPreTest(CONTEXT IndexContext, st_INDEX StIndex, TERM Term)
/**************************************************************
INPUT:
RETURNS:
EFFECTS:
***************************************************************/
{
SYMBOL FirstDomain;
POINTER Result;
#ifdef CHECK
if (!st_StackEmpty(st_STACKSAVE)) {
misc_StartErrorReport();
misc_ErrorReport("\n In st_ExistGenPreTest: ST-Stack not empty.\n");
misc_FinishErrorReport();
}
else
if (st_CURRENT_RETRIEVAL != st_NOP) {
misc_StartErrorReport();
misc_ErrorReport("\n In st_ExistGenPreTest: %d Retrieval already in progress.\n",
st_CURRENT_RETRIEVAL);
misc_FinishErrorReport();
}
#endif
cont_Check();
if (st_Exist(StIndex)) {
st_CURRENT_RETRIEVAL = st_GENPRETEST;
st_WHICH_CONTEXTS = st_STANDARD;
st_INDEX_CONTEXT = IndexContext;
st_STACKSAVE = st_StackBottom();
FirstDomain = symbol_FirstIndexVariable();
st_EXIST_MINMAX = term_ComputeSize(Term);
cont_CreateBinding(IndexContext, FirstDomain, IndexContext, Term);
cont_StartBinding();
st_StackPush(StIndex->subnodes);
cont_StartBinding();
Result = st_TraverseForExistGenPreTest(IndexContext);
#ifdef CHECK
cont_SaveState();
#endif
if (Result == NULL)
st_CancelExistRetrieval();
return Result;
} else
return NULL;
}
BOOL cont_BindingsAreRenamingModuloMatching(const CONTEXT RenamingContext)
{
CONTEXT Context;
#ifdef CHECK
if (!cont_IsContextEmpty(RenamingContext)) {
misc_StartErrorReport();
misc_ErrorReport("\n In cont_BindingsAreRenamingModuloMatching:");
misc_ErrorReport(" Renaming context contains bindings.\n");
misc_FinishErrorReport();
}
#endif
cont_StartBinding();
Context = cont_LastBinding();
while (Context) {
if (!symbol_IsIndexVariable(cont_BindingSymbol(Context))) {
SYMBOL CodomainSymbol;
CodomainSymbol = term_TopSymbol(cont_BindingTerm(Context));
if (symbol_IsVariable(CodomainSymbol)) {
if (cont_VarIsRenamed(RenamingContext, CodomainSymbol)) {
cont_BackTrack();
return FALSE;
} else {
cont_CreateBinding(RenamingContext, CodomainSymbol, NULL, NULL);
cont_SetContextBindingRenaming(RenamingContext, CodomainSymbol, CodomainSymbol);
}
} else {
cont_BackTrack();
return FALSE;
}
}
Context = cont_BindingLink(Context);
}
cont_BackTrack();
return TRUE;
}
LIST st_GetInstancePreTest(CONTEXT IndexContext, st_INDEX StIndex, TERM Term)
/**************************************************************
INPUT:
RETURNS:
EFFECTS:
***************************************************************/
{
LIST Result;
SYMBOL FirstDomain;
cont_Check();
FirstDomain = symbol_FirstIndexVariable();
cont_CreateBinding(IndexContext, FirstDomain, IndexContext, Term);
Result = st_TraverseTreeInstancePreTest(IndexContext, StIndex, term_ComputeSize(Term));
cont_Reset();
return Result;
}
LIST st_GetGen(CONTEXT IndexContext, st_INDEX StIndex, TERM Term)
/**************************************************************
INPUT:
RETURNS:
EFFECTS:
***************************************************************/
{
LIST Result;
SYMBOL FirstDomain;
cont_Check();
FirstDomain = symbol_FirstIndexVariable();
cont_CreateBinding(IndexContext, FirstDomain, cont_InstanceContext(), Term);
Result = st_TraverseTreeGen(IndexContext, StIndex);
cont_Reset();
return Result;
}
BOOL st_EntryDelete(st_INDEX StIndex, POINTER Pointer, TERM Term, const CONTEXT Context)
/**************************************************************
INPUT:
RETURNS:
EFFECTS:
***************************************************************/
{
BOOL Found;
LIST Subnodes;
SYMBOL FirstDomain;
cont_Check();
FirstDomain = symbol_FirstIndexVariable();
cont_CreateBinding(Context, FirstDomain, Context, Term);
for (Found = FALSE, Subnodes = StIndex->subnodes;
list_Exist(Subnodes);
Subnodes = list_Cdr(Subnodes)) {
st_INDEX CurrentNode;
CurrentNode = (st_INDEX)list_Car(Subnodes);
cont_StartBinding();
if (subst_Variation(Context, CurrentNode->subst)) {
list_Rplaca(Subnodes, st_EntryDeleteHelp(Context, CurrentNode, Pointer, &Found));
if (Found) {
StIndex->subnodes = list_PointerDeleteElement(StIndex->subnodes, NULL);
if (list_Exist(StIndex->subnodes)) {
CurrentNode = (st_INDEX)list_Car(StIndex->subnodes);
st_SetMax(StIndex, st_Max(CurrentNode));
st_SetMin(StIndex, st_Min(CurrentNode));
for (Subnodes = list_Cdr(StIndex->subnodes);
list_Exist(Subnodes);
Subnodes = list_Cdr(Subnodes)) {
CurrentNode = (st_INDEX)list_Car(Subnodes);
if (st_Max(CurrentNode) > st_Max(StIndex))
st_SetMax(StIndex, st_Max(CurrentNode));
if (st_Min(CurrentNode) < st_Min(StIndex))
st_SetMin(StIndex, st_Min(CurrentNode));
}
} else {
st_SetMax(StIndex, 0);
st_SetMin(StIndex, 0);
}
break;
}
}
cont_BackTrack();
}
cont_Reset();
return Found;
}
void st_EntryCreate(st_INDEX StIndex, POINTER Pointer, TERM Term, const CONTEXT Context)
/**************************************************************
INPUT:
RETURNS:
EFFECTS:
***************************************************************/
{
st_INDEX Current;
st_INDEX BestNonVariant;
SYMBOL FirstDomain;
st_MINMAX MinMax;
cont_Check();
MinMax = term_ComputeSize(Term);
/* CREATE INITIAL BINDING AND INITIALIZE LOCAL VARIABLES */
FirstDomain = cont_NextIndexVariable(Context);
cont_CreateBinding(Context, FirstDomain, Context, Term);
Current = StIndex;
if (st_Max(Current) < MinMax)
st_SetMax(Current, MinMax);
else if (st_Min(Current) > MinMax)
st_SetMin(Current, MinMax);
/* FIND "LAST" VARIATION */
while (!st_IsLeaf(Current) &&
(Current = st_FirstVariant(Context, Current->subnodes, &BestNonVariant))) {
if (st_Max(Current) < MinMax)
st_SetMax(Current, MinMax);
else if (st_Min(Current) > MinMax)
st_SetMin(Current, MinMax);
StIndex = Current;
}
if (cont_BindingsSinceLastStart()==0 && Current && st_IsLeaf(Current)) {
/* INSERT ENTRY EQUAL MODULO RENAMING */
Current->entries = list_Cons(Pointer, Current->entries);
} else if (BestNonVariant) {
/* CREATE INNER NODE AND A NEW LEAF */
SUBST ComGen, SubstOld, SubstNew;
if (!st_IsLeaf(BestNonVariant))
st_CloseUsedVariables(Context, BestNonVariant->subnodes);
ComGen = subst_ComGen(Context, BestNonVariant->subst, &SubstOld, &SubstNew);
st_NodeAddInner(BestNonVariant,
SubstOld,
subst_CloseOpenVariables(SubstNew),
ComGen,
MinMax,
Pointer);
} else
/* ADD A SINGLE LEAF NODE TO FATHER */
StIndex->subnodes =
list_Cons(st_NodeAddLeaf(subst_CloseOpenVariables(subst_Nil()), MinMax,
Pointer),
StIndex->subnodes);
cont_Reset();
}