OBJECT_ID iter_NextNow(ITER_ID iter_id,VM_ID vm_id)
{
OBJECT_ID next = iter_Next(iter_id,vm_id);
if(obj_GetType(next) == TYPE_BLOCK) //used only to differentiate between an object to return and a generator not finished
{
struct _vm *vm = (struct _vm*)mem_lock(vm_id);
iter_object *iter = (iter_object*)mem_lock(iter_id);
OBJECT_ID ret = 0;
BLOCK_ID bo = iter->tag;
iter_RestoreBlockStack(iter_id,vm_id);
obj_IncRefCount(iter_id);
while(ret == 0)//TODO doesnt stop after one block
{
ret = vm_Step(vm_id,0);
if(!stack_Contains(vm->blocks,bo)) //via normal return
//TODO switch to integer comparison to block stack num with the block stack num at the beginning
{
BLOCK_ID n = stack_Top(vm->blocks);
if(!stack_IsEmpty(vm->blocks))
{
block_object *bn = (block_object*)mem_lock(n);
ret = stack_Pop(bn->stack);
mem_unlock(n,0);
}
iter_ClearBlockStack(iter_id,vm_id);
break;
}
else if(ret != 0) //via yield
{
iter_SaveBlockStack(iter_id,vm_id);
obj_DecRefCount(ret);
}
}
mem_unlock(iter_id,0);
mem_unlock(vm_id,0);
obj_DecRefCount(iter_id);
return(ret);
}
obj_DecRefCount(next);
return(next);
}
static int kbo_CompVarCondAndWeight(TERM Term1, BOOL *VarCond1, TERM Term2, BOOL *VarCond2)
/**************************************************************
INPUT: Two terms and two pointers to booleans.
EFFECT: Sets the booleans with respect to the kbo variable condition.
Computes the kbo weight difference.
***************************************************************/
{
SYMBOL MaxVar1,MaxVar2;
TERM Term;
LIST Scan;
int i,Stack,Weight;
*VarCond1 = *VarCond2 = TRUE;
MaxVar1 = term_MaxVar(Term1);
MaxVar2 = term_MaxVar(Term2);
Stack = stack_Bottom();
Weight = 0;
if (MaxVar1 < MaxVar2)
MaxVar1 = MaxVar2;
for (i = 0; i <= MaxVar1; i++) {
ord_VARCOUNT[i][0] = 0;
ord_VARCOUNT[i][1] = 0;
}
Term = Term1;
if (term_IsStandardVariable(Term)) {
ord_VARCOUNT[term_TopSymbol(Term)][0]++;
Weight += kbo_MINWEIGHT;
}
else {
Weight += symbol_Weight(term_TopSymbol(Term));
if (term_IsComplex(Term))
stack_Push(term_ArgumentList(Term));
}
while (!stack_Empty(Stack)) {
Scan = stack_Top();
Term = (TERM)list_Car(Scan);
stack_RplacTop(list_Cdr(Scan));
if (term_IsStandardVariable(Term)) {
Weight += kbo_MINWEIGHT;
ord_VARCOUNT[term_TopSymbol(Term)][0]++;
}
else {
Weight += symbol_Weight(term_TopSymbol(Term));
if (term_IsComplex(Term))
stack_Push(term_ArgumentList(Term));
}
while (!stack_Empty(Stack) && list_Empty(stack_Top()))
stack_Pop();
}
Term = Term2;
if (term_IsStandardVariable(Term)) {
Weight -= kbo_MINWEIGHT;
ord_VARCOUNT[term_TopSymbol(Term)][1]++;
}
else {
Weight -= symbol_Weight(term_TopSymbol(Term));
if (term_IsComplex(Term))
stack_Push(term_ArgumentList(Term));
}
while (!stack_Empty(Stack)) {
Scan = stack_Top();
Term = (TERM)list_Car(Scan);
stack_RplacTop(list_Cdr(Scan));
if (term_IsStandardVariable(Term)) {
Weight -= kbo_MINWEIGHT;
ord_VARCOUNT[term_TopSymbol(Term)][1]++;
}
else {
Weight -= symbol_Weight(term_TopSymbol(Term));
if (term_IsComplex(Term))
stack_Push(term_ArgumentList(Term));
}
while (!stack_Empty(Stack) && list_Empty(stack_Top()))
stack_Pop();
}
for (i = 0; i <= MaxVar1; i++) {
if (ord_VARCOUNT[i][0] < ord_VARCOUNT[i][1]) {
*VarCond1 = FALSE;
if (!*VarCond2)
return Weight;
}
if (ord_VARCOUNT[i][0] > ord_VARCOUNT[i][1]) {
*VarCond2 = FALSE;
if (!*VarCond1)
return Weight;
}
}
return Weight;
}