Re: [Boost-users] type_with_alignment

14 Jun 2006

      On Jun 14, 2006, at 4:56 AM, John Maddock wrote:
...
Gottlob Frege wrote:
...
...
if unknown_struct is an incomplete type (which is what I meant, and
should have said), alignment_of doesn't compile.
If the type is incomplete then you can't use aligned_storage  
anyway, since
you don't know how much storage you'll need!  Sorry but you've lost  
me now.
There are applications such as boost::function where aligned storage  
for an unknown type is useful.  In boost::function's case, aligned  
storage could be used to implement the "short string optimization".   
The general pattern is:

class Container
{
private:
     const unsigned buf_size = ...;
     aligned_storage::type buffer;
public:
     template <class T>
        Container(const T& t) {/* might stick t into buffer instead  
of on heap, based on sizeof(T) */}
};

On Jun 14, 2006, at 6:55 AM, David Abrahams wrote:
...
I think what the OP is looking for is called boost::shared_ptr ;-)
shared_ptr can't compete with this application performance-wise.

-Howard

Re: [Boost-users] type_with_alignment

Howard Hinnant