Re: copy conctructor?

From:
"Jonathan Mcdougall" <jonathanmcdougall@gmail.com>
Newsgroups:
comp.lang.c++
Date:
18 May 2006 13:06:30 -0700
Message-ID:
<1147982790.041356.198290@i39g2000cwa.googlegroups.com>
asifalli.khan@gmail.com wrote:

Hi,


Please learn to quote correctly
(http://en.wikipedia.org/wiki/Top-posting and
http://cfaj.freeshell.org/google/ if you use Google Groups).

is there any name to those 4 type of copy conctructor.


No, they are all copy constructors.

1)Is there any conctructor exits named syclo or clone conctructor.


Cloning an object is more an idiom than a language feature. Cloning (as
opposed to copy-constructing) is important when all you have is a
pointer to a base class and you must copy the object. Since you have no
way of knowing the object's original type, the easiest way would be to
add a virtual function clone() that would return a new object on the
heap.

# include <memory>

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

class derived_1 : public base
{
public:
  virtual derived_1* clone()
  {
    return new derived_1(*this);
  }
};

class derived_2 : public base
{
public:
  virtual derived_2* clone()
  {
    return new derived_2(*this);
  }
};

void f(base& b)
{
  // I want to copy 'b', but what is it?
  // ah!
  std::auto_ptr<base> bb(b.clone());
}

I never heard of a "syclo" constructor.

Jonathan

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