我正在移植一个非常大的代码库，我在处理旧代码时遇到了更多困难。
例如，这会导致编译器错误:
inline CP_M_ReferenceCounted *
FrAssignRef(CP_M_ReferenceCounted * & to, CP_M_ReferenceCounted * from)
{
if (from) from->AddReference();
if (to) to->RemoveReference();
to = from;
return to;
}
错误是:错误:'*' 标记之前的预期初始值设定项。
我怎么知道这是什么。我查看了内联成员函数以确保我理解，我认为内联不是原因，但我不确定是什么原因。
另一个例子:
template <class eachClass>
eachClass FrReferenceIfClass(FxRC * ptr)
{
eachClass getObject = dynamic_cast<eachClass>(ptr);
if (getObject) getObject->AddReference();
return getObject;
}
错误是:错误:'eachClass FrReferenceIfClass'的模板声明
就是这样。我如何决定这是什么？诚然，我对模板感到生疏。
更新:
这是 CP_M_ReferenceCounted:
#pragma once
#ifndef _H_CP_M_RefCounted
#define _H_CP_M_RefCounted
// CPLAT_Framework
#include "CP_Types.h"
CPLAT_Begin_Namespace_CPLAT
/*!
* @class CP_M_RefCounted
* @brief Mix-in class for objects that are reference counted.
*/
class CP_EXPORT CP_M_RefCounted
{
public:
//! @name Reference
//@{
UInt32 AddReference() const;
UInt32 RemoveReference() const;
//@}
//! @name Autorelease
//@{
void Autorelease() const;
//@}
//! @name Getters
//@{
/*!
* Returns the current ref count.
*
* @exception none
*
* @return UInt32 The current referencce count.
*/
UInt32 GetRefCount() const { return( fRefCount ); }
//@}
//! @name operators
//@{
CP_M_RefCounted& operator = ( const CP_M_RefCounted& inRefCounted );
//@}
protected:
//! @name Constructor / Destructor
//@{
//! Constructor.
CP_M_RefCounted();
CP_M_RefCounted( CP_M_RefCounted& inRefCounted );
//! Destructor.
virtual ~CP_M_RefCounted();
//@}
// class data
private:
mutable UInt32 fRefCount; /*! The number of references to this object. */
//========================================================================
// Platform specific routines
//========================================================================
#if TARGET_OS_MAC
#endif
#if TARGET_OS_WIN32
#endif
#if TARGET_OS_LINUX
#endif
};
template <class T>
inline const T* CP_Autorelease(const T* inObj)
{
if( inObj )
inObj->Autorelease();
return( inObj );
}
template <class T>
inline T* CP_Autorelease(T* inObj)
{
if( inObj )
inObj->Autorelease();
return( inObj );
}
/*!
* @class CP_SmartRef
* @brief Template class representing a smart pointer for reference counted objects.
*/
template <class T>
class CP_SmartRef
{
public:
//! @name Constructor / Destructor
//@{
//! Constructor.
CP_SmartRef()
: fObj(NULL) {}
CP_SmartRef(
T *inObj,
bool inTransferOwnership=false )
: fObj(inObj) { if( !inTransferOwnership && fObj ) fObj->AddReference(); }
CP_SmartRef( const CP_SmartRef<T>& inRef )
: fObj(inRef.fObj) { if( fObj ) fObj->AddReference(); }
template <class Other>
CP_SmartRef( const CP_SmartRef<Other>& inRef )
: fObj(NULL) { T* other = inRef.Get(); this->Reset( other ); } // assignment to local variable should prevent upcasts and cross-casts
//! Destructor.
~CP_SmartRef() { if( fObj ) fObj->RemoveReference(); }
//@}
//! @name operators
//@{
T& operator *() const { return( *fObj ); }
T* operator->() const { return( fObj ); }
operator T *() const { return( fObj ); }
CP_SmartRef<T>& operator = ( const CP_SmartRef<T>& inRef ) { this->Reset( inRef.fObj ); return *this; }
template <class Other>
CP_SmartRef<T>& operator = ( const CP_SmartRef<Other>& inRef ) { this->Reset( inRef.Get() ); return *this; }
CP_SmartRef<T>& operator = ( T* inObj ) { this->Reset( inObj ); return *this; }
template <class Other>
CP_SmartRef<T>& operator = ( Other* inObj ) { this->Reset( inObj ); return *this; }
//@}
//! @name Object management
//@{
T *Get() const { return( fObj ); }
T *Reset(
T *inObj,
bool inTransferOwnership = false );
T *Release();
//@}
// class data
protected:
T *fObj;
//========================================================================
// Platform specific routines
//========================================================================
#if TARGET_OS_MAC
#endif
#if TARGET_OS_WIN32
#endif
#if TARGET_OS_LINUX
#endif
};
template <class T>
T* CP_SmartRef<T>::Reset( T *inObj, bool inTransferOwnership )
{
if ( inObj != fObj )
{
if( fObj )
fObj->RemoveReference();
fObj = inObj;
if( inObj && !inTransferOwnership )
inObj->AddReference();
}
else if( inObj && inTransferOwnership )
{
inObj->RemoveReference();
}
return( fObj );
}
template <class T>
T* CP_SmartRef<T>::Release()
{
T *tmp = fObj;
fObj = NULL;
return( tmp );
}
CPLAT_End_Namespace_CPLAT
#endif // _H_CP_M_RefCounted
最佳答案
我认为您必须对编译器的错误消息产生某种感觉。有更糟的编译器，也有更好的编译器。那个肯定是最糟糕的一个。一个好的将插入符号指向错误发生的地方，并给出可能出错的提示。
例如，在给定的情况下，编译器可能会在到达 CP_M_ReferenceCounted 时停止解析声明的类型，并将其解析为要声明的名称。语法允许这样做，因为一些声明没有给出类型(构造函数就是一个例子)。所以它需要一个该名称的初始值设定项，而不是星号。这暗示 CP_M_ReferenceCounted 可能未声明。检查您包含了正确的 header 。
关于c++ - 如何确定是什么*真正*导致您的编译器错误，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/2503739/