On Mon, Jul 11, 2011 at 10:53 PM, Edward Diener <eldiener@tropicsoft.com> wrote:
On 7/11/2011 9:32 PM, Lorenzo Caminiti wrote:
Let's write down some examples for what I meant with comment #5 leaving variadics (comment #6) and implementation issues a side for a moment. Let's just try to see if (1) we understand each other and (2) we list options that users will find to be a better interface for the library. I will not list the trait parameter (even if I suggested to always add it).
Here's some examples of what I was proposing with my comment #5:
// check if mytpl exist TTI_TEMPLATE( mytpl ) // [1]
// check if template<class> struct mytpl exist TTI_TEMPLATE( template( (class) ) struct mytpl )
// check if template<class, int> class mytpl exist TTI_TEMPLATE( template( (class) (int) ) class mytpl )
// check if template<class, int, template<typename, class> struct> class mytpl exist TTI_TEMPLATE( template( (class) (int) (template( (typename) (class) ) struct) class mytpl )
The real question still is: For the TTI library user, is the interface above better than TTI_TEMPLATE_CHECK_PARAMS? (Again, you know my answer is yes but that's just my opinion.) I think we should all focus the discussion in try to answer this question first.
I do not like your syntax. I much prefer the syntax I already have, with a separate macro parameter merely being the template parameters if the end-user is looking for a match, ie.
TTI_TEMPLATE(mytpl,BOOST_PP_NIL) TTI_TEMPLATE(mytpl,(class)(int)(template<typename class> struct))
or for variadic macros
TTI_TEMPLATE(mytpl) TTI_TEMPLATE(mytpl,class,int,template<typename class> struct)
OK but don't you need something in between the inner template typename and class? (Because they can be any arbitrary type name for non-type template parameters.) For example (again, leaving variadics a side for a moment): TTI_TEMPLATE(mytpl,BOOST_PP_NIL) TTI_TEMPLATE(mytpl,(class)(int)(template<typename)(class> struct)) // [1] If so, is that better than the following? TTI_TEMPLATE(mytpl,BOOST_PP_NIL) TTI_TEMPLATE(mytpl,(class)(int)(template( (typename)(class) ) struct)) // [2] (You know I (somewhat strongly this time) prefer [2] to [1], see my comment #4. But that's just my opinion.) Thanks, --Lorenzo