Re: [boost] [smart_ptr] make_shared usage

From: Peter Dimov (pdimov_at_[hidden])
Date: 2008-07-27 11:25:34

Daniel Frey:

> Hi,
>
> I have a question on make_shared. Consider a class which intends to
> force all instances to be handled via a shared_ptr. I used to do this by
> putting the ctors into the private section and adding static
> create()-methods in the public section. Example:
>
> class X
> {
> private:
>   X( int, double );
>
> public:
>   static shared_ptr<X> create( int i, double d )
>   {
>      return shared_ptr<X>( new X( i, d ) );
>   }
> };
>
> Replacing the returned expression with make_shared<X>( i, d ) wouldn't
> work, since it requires a public ctor.

You should be able to make it work by making the appropriate make_shared 
overload a friend:

 template< class T, class A1, class A2 >
 friend
 boost::shared_ptr< T > boost::make_shared( A1 const & a1, A2 const & a2 );