Re: [boost] [utility] Any interest for a macro which automatically creates default move-semantics, comparisson etc for a class

Subject: Re: [boost] [utility] Any interest for a macro which automatically creates default move-semantics, comparisson etc for a class
From: Bjorn Reese (breese_at_[hidden])
Date: 2013-11-08 09:20:21

On 11/06/2013 06:38 PM, Viktor Sehr wrote:

> Example usage:
> class Foo {
> public:
>    Foo() {}
>    DEFAULT_EVERYTHING(Foo,
> ( (int)(a) )
>   ( (std::vector<int>)(b) )
> ( (float)(c) )
>    );
> };
>
> Any interest, suggestions or ideas?

If we are going to specify the member variables in a funny way, it may
be worth considering a solution based on Boost.Fusion. For example,
swap() can be made like this:

class Foo {
public:
   Foo()
   {
     member.a = 0;
     member.c = 0.0;
   }

   // swap and swap_functor should be turned into a macro
public:
   void swap(Foo& other)
   {
     using namespace boost::fusion;
     for_each(zip_view< vector2<member_type&, member_type&> 
 >(vector2<member_type&, member_type&>(member, other.member)), 
swap_functor());
   }
private:
   struct swap_functor
   {
     template <typename T>
     void operator()(const boost::fusion::vector2<T,T>& data) const
     {
       using namespace boost::fusion;
       boost::swap(at_c<0>(data), at_c<1>(data));
     }
   };

private:
     BOOST_FUSION_DEFINE_STRUCT_INLINE
     (member_type,
      // Member variables
      (int, a)
      (std::vector<int>, b)
      (float, c)
     )
     member_type member;
};