On Tue, Oct 7, 2008 at 3:06 PM, Joel Falcou <joel.falcou@u-psud.fr> wrote:
Daniel Walker a écrit :
Of course, I think there is a need to package SFINAE techniques as a nice library for compile-time class-based type introspection - something beyond MPL's HAS_XXX. I've done some work on this myself, actually, and I once submitted a patch implementing HAS_XXX for member templates, but I believe it got lost in the SVN migration. This is another topic that doesn't relate to is_range, but yeah, sure, if you have something along these lines, by all means, share it! ;-)
Yeah we kinda miscommunicated on this topic. I'll gather what I have and see what is worth sharing. basically, what I tried to do was a generic
BOOST_HAS_METHOD_NAMED(foo, (int,int))
that check for presence of a given method with a given prototypes in types with variations to catch or not to catch const version of a named methods etc. The code is rather simple IIRC as it's roaming the internet since ages but never put into a proper usable macro I think.
That sounds great. Nice that you handle constness. I would suggest adding support for volatility, as well, but yeah, sounds good so far.
I also think we can check what's needed for this and how to put it properly. If you think it's worth, maybe we should start a new topic and work over this.
Sure! If you have member functions, I have member templates, and member types are already in MPL, then all we lack are macros for member data and member function templates. I would suggest naming the complete set of class-based introspection macros like so: BOOST_HAS_MEMBER_DATA BOOST_HAS_MEMBER_TYPE BOOST_HAS_MEMBER_TEMPLATE BOOST_HAS_MEMBER_FUNCTION BOOST_HAS_MEMBER_FUNCTION_TEMPLATE And of course, if expression SFINAE gets ironed out soon, we could go ahead and add BOOST_HAS_EXPRESSION and perhaps some metafunctions in support of concept-based introspection... or maybe a better term for it would be expression introspection. But one step at a time... Why don't we both package what we have, upload to vault, and then work out merging the two and adding the rest in another thread? Daniel Walker