Thorsten Ottosen:
Joaquin M Lopez Munoz skrev:
Thorsten Ottosen <thorsten.ottosen <at> dezide.com> writes:
I would use it as a lightweight and more convenient replacement for boost::shared_ptr<const T>.
In my application I might have < 50 objects that needs to by flyweights. They are almost never identical, and if they are, the memory occupied by the factory would probably be much larger than that of duplication.
Well, then you might not need using the flyweight idiom after all...
Well, it's lower overhead (if no factory and forwarding constructors/operations makes it a better choice than shared_ptrconst T>.
It might be possible to do this using a custom factory along the lines of: template<class T> struct sp_factory { typedef boost::shared_ptr<T const> handle_type; handle_type insert( T const & t ) { return handle_type( new T( t ) ); } void erase( handle_type ) {} T const & entry( handle_type p ) { return *p; } }; but there's no way to tell from the documentation; it never describes how the Factory template parameter is actually used. http://svn.boost.org/svn/boost/sandbox/flyweight/libs/flyweight/doc/referenc... As I read it, a flyweight<> can ignore all of its template parameters beyond T and still conform to its spec, which is probably not what's intended.