Thanks again for your help. I was also able to get that example to compile,
which was perfect. Unfortunately, it seems rather fragile. I had copied
most of the pieces over into a split test.hpp/test.cpp, and kept getting
errors. I did eventually resolve the problem by more completely replacing
them with your code directly, but I wasn't able to figure out what was
causing the problem. Of course, that means when I tried to apply it to my
real code, I ended up with the same error:
solution.hpp:36:3: error: template argument 1 is invalid
solution.hpp:36:4: error: expected identifier before '::' token
solution.hpp:36:6: error: typedef name may not be a nested-name-specifier
solution.hpp:36:6: error: expected ';' at end of member declaration
solution.hpp:36:11: error: 'type' does not name a type
solution.hpp:52:3: error: template argument 1 is invalid
solution.hpp:52:4: error: expected identifier before '::' token
solution.hpp:52:6: error: typedef name may not be a nested-name-specifier
solution.hpp:52:6: error: expected ';' at end of member declaration
solution.hpp:52:11: error: 'type' does not name a type
the relevant pieces of code were the following:
31 template<class T>
32 struct get_neighborhood_type {
33 typedef typename mpl::eval_if
AMDG
On 03/11/2014 01:42 PM, Samuel Christie wrote:
I'm not sure how to do the get_collection_type deduction in such a way
that
it works for more than one type of collection. I.e., both a vector<T> and a Collection as defined above.
You can either use a nested typedef (like T::iterator) or you can use decltype(boost::declval<T>().collection()).
I also tried to do a test with the slightly more basic vector<Test> collection type. I got close, but I eventually had issues with the != required by the foreach loop pattern.
That shouldn't have been a problem, since equality_comparable defines both == and !=.
Here's a paste of most of the test code: pastebin.com/GiQwQTcq
Hopefully what I'm having trouble with makes sense to you; if not, maybe just providing a few more examples of the pieces required to make a for(auto i : t.collection()) work based on the above class declaration would be helpful. I feel like either I'm getting close, or I'm trying to do something I shouldn't be.
You're really close. I've gotten your example working. See attached. (I also cleaned it up a bit by using BOOST_TYPE_ERASURE_MEMBER/FREE). Tested with MSVC 12 and GCC 4.7.
In Christ, Steven Watanabe
_______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users