C / C++ / MFC

Programm3r wrote:

void (*app_cb) (TFM_PARAM3 TfmParameters); // THIS PART I DONT UNDERSTAND

waldermort wrote:

template <class _t=""> class TCollection

template <class _T> class TCollection {
public:
	TCollection();
	~TCollection();
	_T  at(unsigned int iPos);
	void add(_T T);
	void clear();
	int  size();
	bool empty();
private:
	_T* pData;
	int pCount;
};

TCollection<class _T>::TCollection() : pData(0) , pCount(0)
{
}

TCollection<class _T>::~TCollection()
{
	clear();
}

_T TCollection<class _T>::at(unsigned int iPos)
{
	if (iPos >= 0 && iPos > pCount)
		return pData[iPos];
	else
		return NULL;
}

void TCollection<class _T>::add(_T T)
{
	if (pData) {
		_T *tmp = new _T [pCount+1];
		for (int i=0;i<pCount;i++)
			tmp[i] = pData[i];
		tmp[i] = T;
		delete [] pData;
		pData = tmp;
		pCount++;
	} else {
		pData = new _T [1];
		pData[0] = T;
		pCount++;
	}
}

E:\Program\foo\TCollection.cpp(18) : error C2027: use of undefined type '_T'<br />
        E:\Program\foo\TCollection.cpp(8) : see declaration of '_T'<br />
E:\Program\foo\TCollection.cpp(20) : error C2036: 'class _T *' : unknown size<br />
E:\Program\foo\TCollection.cpp(28) : error C2512: '_T' : no appropriate default constructor available

template<class _T>
_T TCollection::at(unsigned int iPos){...}

template<class _T>
void TCollection::add(_T T){...}

template<class _T> _T TCollection::at(unsigned int iPos)
{
...
}

template<class _T> void TCollection::add(_T T)

E:\Program\foo\TCollection.cpp(17) : error C2955: 'TCollection' : use of class template requires template argument list<br />
        e:\program\foo\tcollection.h(24) : see declaration of 'TCollection'<br />
E:\Program\foo\TCollection.cpp(25) : error C2955: 'TCollection' : use of class template requires template argument list

template<class _T>
_T TCollection<_T>::at(unsigned int iPos){...}
 
template<class _T>
void TCollection<_T>::add(_T T) {...}

toxcct wrote:

template classes inmplementations have to be in the header.

TCollection<int> objTCollection;

waldermort wrote:

I have defined a template class in a header file like so:

waldermort wrote:

Then try to declare the members in the cpp file like so:

<br />
template <class _T> TCollection<_T>::TCollection () : pData(0), pCount(0)<br />
{<br />
}<br />
template <class _T> TCollection<_T>::~TCollection ()<br />
{<br />
      clear();<br />
}<br />