Re: C++ language: Cloneable cl*****

On 7 Maj, 02:43, Mathias Gaunard <loufo...@[EMAIL PROTECTED]
> wrote:
> struct Cloneable
> {
>      virtual std::size_t sizeof_() const = 0; // returns size of object
>      // performs placement-new on p, copying the object
>      virtual void clone(void* p) const = 0;
> };
>
> then, for example
>
> const A& a = B();
> A* copy;
> try
> {
>      copy = static_cast<A*>(::operator new(a.sizeof_()));
>      a.clone(copy);}
> catch(...)
> {
>      ::operator delete(copy);
>      throw;
> }
>
> That way the user can choose how to allocate the memory.

I am not familiar with in-place construction/destruction, however, I
will keep this example in mid - and come back to it if I need memory
allocation optimizations. Thanks!

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