Russian Qt Forum

class Clonable
{
public:
    virtual Clonable* clone() const = 0;
};

void Copy(const Clonable* src, Clonable** dst, size_t num)
{
 for (size_t i = 0; i < num; ++i) dst[i] = src[i]->clone();
}

class Exception : public std::exception
{
public:
...
  Exception* clone() const
  {
    Exception* result = createClone();
	// check that a descendant overides createClone()
    assert(typeid(*result) == typeid(*this) && " (createClone() is not overrided)"); 
    return result;  
  }

private:
...
  virtual Exception* createClone() const
  {
    return new Exception(*this);  // copy ctor
  }
};


class InvalidArgumentException : public Exception
{
...
private:
  virtual InvalidArgumentException* createClone() const
  {
    return new InvalidArgumentException(*this);
  }

class Foo : public Clonable
{
  int x() const { ... }
...
}

std::vector<Foo*> dst(Count);
copy(src, &dst[0], Count);  // initialize array
dst[0]->x();

class Foo1 : public Clonable
{
  int y() const { ... }
...
}


std::vector<Foo1*> dst1(Count);
copy(src1, &dst1[0], Count);  // initialize array
dst[0]->y();

struct Foo1
{
  double x;
  ...
}

struct Foo2
{
  int x;
  ...
}

template <typename T1, typename T2>
void copyItem(const T1& src, T& dst)
{
  dst.x = src.x;
  ...
}

struct Base {}

struct Foo1 : public Base
{
  double x;
  ...
}

struct Foo2 : public Base
{
  int x;
  ...
}

...
Foo1 foo1;
Foo2 foo2 = foo1;

template <typename T1, typename T2>
void copyItem(const T1& src, T& dst)
{
  dst.x = src.x;
  ...
}