//this file - XHandler.h
class XHandler {
	public:
		XHandler(char *s,char *f,int l) ( //set string,file and line number }
		~XHandler() { //free mem }
		std::ostream &GetException() { //print error stuff }
	private:
		char *str;
		char *file;
		int line;
};

//this file - myclass.h
#include "XHandler.h"
class myclass {
	public:
		...
		void dosomething();
		...
};

void myclass::dosomething() {
	//something bad happened
	throw XHandler("bad!!!",__FILE__,__LINE__);
	...
}

//this file - main.cpp
int main() {
	myclass c;

	c.dosomething(); //force to throw exception
					 //it would be nice to set the exception
					 //details according to this actual file

	} catch(XHandler x) {
		cout << x.GetException(cout);
	}

	return 0;
}

class myclass
{
    public:

          void dosomething(const char *, int);
}

void myclass::dosomething(const char *f, int c)
{
    throw XHandler("bad!!!",f,c);
}

int main()
{
     myclass c;
     try
     {
         c.dosomething(__FILE__, __LINE__);
     }
     catch(XHandler x) {
		// whatever 
	}
}

class vector {
        public:
                ...
                vector operator/(float) const;
                ...
};

vector vector::operator/(float scalar) const {
        if(scalar == 0.0)
                throw XHandler("divide by zero");
        ...
}

int main() {
        vector v(3.0,3.34,8.3);
        try {
                vector newVec = v/0; //cause an exception - how to
                                                //find actual line where this occured???
        ...
        } catch(XHandler x) {
                ...
        }
};