Jason Hise wrote:
Jonathan Turkanis wrote:
I suggested you follow policy_ptr and use mpl metafunction classes as policy template parameters. See, for instance, the array storage policy: http://tinyurl.com/6tbhu.
It looks like this:
template <typename T> class array_storage_ { ... };
struct array_storage { typedef storage_policy_tag policy_category;
template <typename T> struct apply { typedef array_storage_<T> type; }; };
Jonathan
is this essentially the equivalent of the standard allocator's rebind?
The difference is that an allocator is designed *both* to be used by itself and to generate other allocator types. A metafunction class is generally just a type generator. (In the above example there is also some auxilliary machinery to support identifying template arguments by category rather than position.) Jonathan