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template class

jazpearson (47)
Ok - so i'm attempting to create a template class, for creating arrays. Sort of a bit like what vector does, but specific to my needs. More than anything, it's an exercise in creating templates. However, i cannot get the following to compile, and i can't see where i've gone wrong.........

This is a bit more advanced than anything i've ever done before, so any help on this is greatly appreciated. 


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template <typename T> 
class FixedArray {

public:

	FixedArray(int initSize = 0);
	FixedArray(FixedArray<T>& other);
	~FixedArray(void);

	int Find(T& value);

	T* Start()      { return mBuffer; } 
	int GetLength() { return mLength; }

	BOOL SetLength(int newLength); 

	T& operator [](int index) {return mBuffer[index]};

	FixedArray<T>& operator =(FixedArray<T>& other); 

protected:

	T* mBuffer;
	int mLength;

};


template <typename T>
FixedArray<T>::FixedArray(int initSize) 
{
	mBuffer = NULL;
	mLength = 0;
	SetLength(initSize);
}

template <typename T>
FixedArray<T>::FixedArray(FixedArray<T>& other)
{

	mBuffer = NULL;
	mLength = 0;
	*this = other;

}

template <typename T>
FixedArray<T>::~FixedArray(void)
{
	SetLength(0);

}

template <typename T>
int FixedArray<T>::Find(T& value)
{
	int rv=-1;
	for (int lp=0; rv<0 && lp<mLength; lp++)
	{
		if (mBuffer[lp]==value)
			rv=lp;
	}
	return rv;
}

template <typename T>
BOOL FixedArray<T>::SetLength(int newLength)   //using BOOL rather than bool
{

	if (newLength != mLength) 
	{
		if (newLength == 0)
		{
			free(mBuffer);
			mBuffer=NULL;		
		}
		else 
		{
			if (mLength == 0) 
		    {
				mBuffer = (T*) malloc(newLength * sizeof(T));
			}
			else
			{
				mBuffer = (T*) realloc(mBuffer, newLength * sizeof(T));
			}
		}
		mLength=newLength;
	}

return TRUE;

}

template <typename T>
FixedArray<T>& FixedArray<T>::operator =(FixedArray<T>& other)
{
	SetLength(other.mLength);
	memcpy(mBuffer,other.mBuffer, mLength * sizeof(T));
	return *this;
}


class point2d{

public:

	point2d() {};// default constructor
	~point2d(); // destructor

  float distance(point2d p);
  float mX,mY; // member variables

};

typedef FixedArray<point2d> point2darray;
typedef FixedArray<int>     intfixedarray;
typedef FixedArray<float>   floatfixedarray;


point2d::~point2d(void){
	// nothing in here, yet
}

float point2d::distance(point2d p){

  float dist=0;
  float x=0, y=0;
  
  x=(mX-p.mX);
  y=(mY-p.mY);
  dist=sqrt((x*x)+(y*y)); // calculates the distance between 2 points

  return dist;
}


int main(void)

{

	return 0;
}


--------------------------------------------------------------------------

with some of the errors being:




1>c:\program files (x86)\microsoft visual studio 9.0\vc\include\codeanalysis\sourceannotations.h(47) : error C2011: 'vc_attributes::YesNoMaybe' : 'enum' type redefinition
1> c:\program files\microsoft visual studio 9.0\vc\include\codeanalysis\sourceannotations.h(47) : see declaration of 'vc_attributes::YesNoMaybe'
1>c:\program files (x86)\microsoft visual studio 9.0\vc\include\codeanalysis\sourceannotations.h(57) : error C2011: 'vc_attributes::AccessType' : 'enum' type redefinition
1> c:\program files\microsoft visual studio 9.0\vc\include\codeanalysis\sourceannotations.h(57) : see declaration of 'vc_attributes::AccessType'
1>c:\program files (x86)\microsoft visual studio 9.0\vc\include\codeanalysis\sourceannotations.h(71) : error C2011: 'vc_attributes::Pre' : 'struct' type redefinition
1> c:\program files\microsoft visual studio 9.0\vc\include\codeanalysis\sourceannotations.h(71) : see declaration of 'vc_attributes::Pre'
coder777 (8444)
Line 8/20 should be const FixedArray<T>& other
Line 18: T& operator [](int index) {return mBuffer[index];} // Note: ; after mBuffer[index]; not } This might have caused the errors

If you pass a reference (by &) better make it const except you really want that that obect is modified
jazpearson (47)
ah, excellent - it was the ; in the wrong place!! typical :)

thanks very much!
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