C++ CCLinkedList::Discard方法代码示例

ICCItem *CCodeChain::CreateVectorGivenContent(TArray<int> vShape, CCLinkedList *pContentList)

//	CreateVectorGivenContent (new)
//
//	Creates a vector with given shape and content

{
	int i;
	CCVector *pVector;
	ICCItem *pItem;

	pItem = m_VectorPool.CreateItem(this);
	if (pItem->IsError())
		return pItem;
	pItem->Reset();

	pVector = dynamic_cast<CCVector *>(pItem);
	pVector->SetContext(this);

	pVector->SetShape(this, vShape);

	pItem = pContentList->GetFlattened(this, NULL);
	if (pItem->IsError())
	{ 
		pVector->Discard(this);
		return pItem;
	};
	CCLinkedList *pFlattenedContentList = dynamic_cast<CCLinkedList *>(pItem);

	TArray<double> vDataArray;
	for (i = 0; i < pFlattenedContentList->GetCount(); i++)
	{
		vDataArray.Insert(pFlattenedContentList->GetElement(i)->GetDoubleValue());
	};
	pVector->SetArrayData(this, vDataArray);

	//	Done
	pFlattenedContentList->Discard(this);
	return pVector->Reference();
}

ICCItem *fnApply (CEvalContext *pCtx, ICCItem *pArguments, DWORD dwData)

//	fnApply
//
//	Applies the given parameter list to the lambda expression
//
//	(apply exp arg1 arg2 ... argn list)

	{
	CCodeChain *pCC = pCtx->pCC;
	ICCItem *pArgs;
	ICCItem *pResult;
	ICCItem *pFunction;
	ICCItem *pLast;
	CCLinkedList *pList;
	int i;

	//	Evaluate the arguments and validate them

	pArgs = pCC->EvaluateArgs(pCtx, pArguments, CONSTLIT("v*"));
	if (pArgs->IsError())
		return pArgs;

	//	We better have at least two arguments

	if (pArgs->GetCount() < 2)
		{
		pArgs->Discard(pCC);
		return pCC->CreateError(CONSTLIT("apply needs a function and a list of arguments."), NULL);
		}

	//	The last argument better be a list

	pLast = pArgs->GetElement(pArgs->GetCount() - 1);
	if (!pLast->IsList())
		{
		pArgs->Discard(pCC);
		return pCC->CreateError(CONSTLIT("Last argument for apply must be a list."), NULL);
		}

	//	The first argument is the function

	pFunction = pArgs->Head(pCC);

	//	Create a new list to store the arguments in

	pResult = pCC->CreateLinkedList();
	if (pResult->IsError())
		{
		pArgs->Discard(pCC);
		return pResult;
		}

	pList = (CCLinkedList *)pResult;

	//	Add each of the arguments except the last

	for (i = 1; i < pArgs->GetCount() - 1; i++)
		{
		pList->Append(pCC, pArgs->GetElement(i), &pResult);
		if (pResult->IsError())
			{
			pList->Discard(pCC);
			pArgs->Discard(pCC);
			return pResult;
			}

		pResult->Discard(pCC);
		}

	//	Add each of the elements of the last list

	for (i = 0; i < pLast->GetCount(); i++)
		{
		pList->Append(pCC, pLast->GetElement(i), &pResult);
		if (pResult->IsError())
			{
			pList->Discard(pCC);
			pArgs->Discard(pCC);
			return pResult;
			}

		pResult->Discard(pCC);
		}

	//	Set the literal flag to indicate that the arguments should
	//	not be evaluated.

	pList->SetQuoted();

	//	Execute the function

	if (pFunction->IsFunction())
		pResult = pFunction->Execute(pCtx, pList);
	else
		pResult = pFunction->Reference();

	pList->Discard(pCC);

	//	Done
//.........这里部分代码省略.........

ICCItem *fnLinkedList (CEvalContext *pCtx, ICCItem *pArguments, DWORD dwData)

//	fnLinkedList
//
//	Handles linked-list specific functions
//
//	(lnkAppend linked-list item) -> list
//	(lnkRemove linked-list index) -> list
//	(lnkRemoveNil linked-list) -> list
//	(lnkReplace linked-list index item) -> list
//
//	HACK: This function has different behavior depending on the first
//	argument. If the first argument is a variable holding a linked list,
//	then the variable contents will be changed. If the variable holds Nil,
//	then the variable contents are not changed. In all cases, the caller
//	should structure the call as: (setq ListVar (lnkAppend ListVar ...))
//	in order to handle all cases.

	{
	CCodeChain *pCC = pCtx->pCC;
	ICCItem *pArgs;
	ICCItem *pList;
	CCLinkedList *pLinkedList;
	ICCItem *pResult;

	//	Evaluate the arguments

	if (dwData == FN_LINKEDLIST_APPEND)
		pArgs = pCC->EvaluateArgs(pCtx, pArguments, CONSTLIT("lv"));
	else if (dwData == FN_LINKEDLIST_REMOVE_NIL)
		pArgs = pCC->EvaluateArgs(pCtx, pArguments, CONSTLIT("l"));
	else
		pArgs = pCC->EvaluateArgs(pCtx, pArguments, CONSTLIT("liv"));
	if (pArgs->IsError())
		return pArgs;

	//	Get the linked list

	pList = pArgs->GetElement(0);
	if (pList->GetClass()->GetObjID() == OBJID_CCLINKEDLIST)
		pLinkedList = (CCLinkedList *)pList->Reference();
	else if (pList->IsNil())
		{
		pList = pCC->CreateLinkedList();
		if (pList->IsError())
			{
			pArgs->Discard(pCC);
			return pList;
			}
		pLinkedList = (CCLinkedList *)pList;
		}
	else
		{
		pArgs->Discard(pCC);
		return pCC->CreateError(CONSTLIT("Linked-list expected:"), NULL);
		}

	//	Do the right thing

	switch (dwData)
		{
		case FN_LINKEDLIST_APPEND:
			{
			ICCItem *pItem = pArgs->GetElement(1);
			ICCItem *pError;

			pLinkedList->Append(pCC, pItem, &pError);
			if (pError->IsError())
				{
				pLinkedList->Discard(pCC);
				pResult = pError;
				}
			else
				{
				pError->Discard(pCC);
				pResult = pLinkedList;
				}
			break;
			}

		case FN_LINKEDLIST_REMOVE:
			{
			int iIndex = pArgs->GetElement(1)->GetIntegerValue();

			//	Make sure we're in range

			if (iIndex < 0 || iIndex >= pLinkedList->GetCount())
				{
				pLinkedList->Discard(pCC);
				pResult = pCC->CreateError(CONSTLIT("Index out of range:"), pArgs->GetElement(1));
				}
			else
				{
				pLinkedList->RemoveElement(pCC, iIndex);
				pResult = pLinkedList;
				}

			break;
			}

//.........这里部分代码省略.........

ICCItem *CCodeChain::EvaluateArgs (CEvalContext *pCtx, ICCItem *pArgs, const CString &sArgValidation)

//	EvaluateArgs
//
//	Evaluate arguments and validate their types

	{
	ICCItem *pArg;
	ICCItem *pNew;
	ICCItem *pError;
	CCLinkedList *pEvalList;
	char *pValidation;
	int i;
	BOOL bNoEval;

	//	If the argument list if quoted, then it means that the arguments
	//	have already been evaluated. This happens if we've been called by
	//	(apply).

	bNoEval = pArgs->IsQuoted();

	//	Create a list to hold the results

	pNew = CreateLinkedList();
	if (pNew->IsError())
		return pNew;

	pEvalList = dynamic_cast<CCLinkedList *>(pNew);

	//	Start parsing at the beginning

	pValidation = sArgValidation.GetPointer();

	//	If there is a '*' in the validation, figure out
	//	how many arguments it represents

	int iVarArgs = Max(0, pArgs->GetCount() - (sArgValidation.GetLength() - 1));

	//	Loop over each argument

	for (i = 0; i < pArgs->GetCount(); i++)
		{
		ICCItem *pResult;

		pArg = pArgs->GetElement(i);

		//	If we're processing variable args, see if we're done

		if (*pValidation == '*')
			{
			if (iVarArgs == 0)
				pValidation++;
			else
				iVarArgs--;
			}

		//	Evaluate the item. If the arg is 'q' or 'u' then we 
		//	don't evaluate it.

		if (bNoEval || *pValidation == 'q' || *pValidation == 'u')
			pResult = pArg->Reference();

		//	If the arg is 'c' then we don't evaluate unless it is
		//	a lambda expression (or an identifier)

		else if (*pValidation == 'c' && !pArg->IsLambdaExpression() && !pArg->IsIdentifier())
			pResult = pArg->Reference();

		//	Evaluate

		else
			{
			pResult = Eval(pCtx, pArg);

			//	We don't want to return on error because some functions
			//	might want to pass errors around

			if (*pValidation != 'v' && *pValidation != '*')
				{
				if (pResult->IsError())
					{
					pEvalList->Discard(this);
					return pResult;
					}
				}
			}

		//	Check to see if the item is valid

		switch (*pValidation)
			{
			//	We expect a function...

			case 'f':
				{
				if (!pResult->IsFunction())
					{
					pError = CreateError(LITERAL("Function expected"), pResult);
					pResult->Discard(this);
					pEvalList->Discard(this);
//.........这里部分代码省略.........

ICCItem *CCodeChain::Link (const CString &sString, int iOffset, int *retiLinked, int *ioiCurLine)

//	Link
//
//	Parses the given string and converts it into a linked
//	chain of items

	{
	char *pStart;
	char *pPos;
	ICCItem *pResult = NULL;
	int iCurLine = (ioiCurLine ? *ioiCurLine : 1);

	pStart = sString.GetPointer() + iOffset;
	pPos = pStart;

	//	Skip any whitespace

	pPos = SkipWhiteSpace(pPos, &iCurLine);

	//	If we've reached the end, then we have
	//	nothing

	if (*pPos == '\0')
		pResult = CreateNil();

	//	If we've got a literal quote, then remember it

	else if (*pPos == SYMBOL_QUOTE)
		{
		int iLinked;

		pPos++;

		pResult = Link(sString, iOffset + (pPos - pStart), &iLinked, &iCurLine);
		if (pResult->IsError())
			return pResult;

		pPos += iLinked;

		//	Make it a literal

		pResult->SetQuoted();
		}

	//	If we've got an open paren then we start a list

	else if (*pPos == SYMBOL_OPENPAREN)
		{
		ICCItem *pNew = CreateLinkedList();
		if (pNew->IsError())
			return pNew;

		CCLinkedList *pList = dynamic_cast<CCLinkedList *>(pNew);

		//	Keep reading until we find the end

		pPos++;

		//	If the list is empty, then there's nothing to do

		pPos = SkipWhiteSpace(pPos, &iCurLine);
		if (*pPos == SYMBOL_CLOSEPAREN)
			{
			pList->Discard(this);
			pResult = CreateNil();
			pPos++;
			}

		//	Get all the items in the list

		else
			{
			while (*pPos != SYMBOL_CLOSEPAREN && *pPos != '\0')
				{
				ICCItem *pItem;
				int iLinked;

				pItem = Link(sString, iOffset + (pPos - pStart), &iLinked, &iCurLine);
				if (pItem->IsError())
					return pItem;

				//	Add the item to the list

				pList->Append(this, pItem, NULL);
				pItem->Discard(this);

				//	Move the position

				pPos += iLinked;

				//	Skip whitespace

				pPos = SkipWhiteSpace(pPos, &iCurLine);
				}

			//	If we have a close paren then we're done; Otherwise we've
			//	got an error of some kind

			if (*pPos == SYMBOL_CLOSEPAREN)
//.........这里部分代码省略.........