Re: copy constructor for class with member pointer
On Jul 11, 6:28 pm, Sergey Lukoshkin <sergey....@gmail.com> wrote:
Hello, everyone!
I faced such a problem. Say I got the class:
class foo
{
public:
foo();
~foo();
private:
T* m_ptr;
};
I need to implement copy constructor. So, the common signature for it
is foo( const& other ). I have to take the pointer from another
object, assign it to this->m_ptr and then make other.m_ptr = 0. But
such a solution discards constness of the other object and signature
of copy constructor should be foo( foo& other ).
Is the approach a correct way to implement the copy constructor for
class with member pointer or not? Loosing constness of argument makes
me hesitating. Thanks.
I do not exactly see what u wanna do but schema described above will
definitely lead to crash.
The usual process is:
1- to construct the ptr with new/allocator
2- destruct with delete/deallocator
struct foo{
foo(){ptr=new bar;};
foo(foo const & x){ptr=new bar(*x.ptr);};
~foo(){delete ptr;};
private:
bar* ptr;
};
but if u need a move-constructor then u gotta read a lot of stuff.
regards,
FM.
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