生成boost绑定表达式

Question

我有以下代码（或类似的东西）来生成绑定表达式。我使用这些表达式以及boost.function_types＆amp; luabind.tag_function将我们框架中的一些函数暴露给lua。

#define BOOST_BIND_ARG(J, I, D) BOOST_PP_CAT(_, BOOST_PP_INC(I))

#define MAKE_BIND_EXPR_GEN(_, N, __)                                         \
template < >                                                                 \
struct MakeBindExpr < N >                                                    \
{                                                                            \
  template < typename FP >                                                   \
  struct result                                                              \
  {                                                                          \
    typedef BOOST_TYPEOF_TPL(boost::bind(                                    \
              FP(0), BOOST_PP_ENUM(N, BOOST_BIND_ARG, BOOST_PP_EMPTY)        \
            )) type;                                                         \
  };                                                                         \
                                                                             \
  template < typename FP >                                                   \
  static typename result < FP >::type get(FP const & f)                      \
  {                                                                          \
    return boost::bind(f, BOOST_PP_ENUM(N, BOOST_BIND_ARG, BOOST_PP_EMPTY)); \
  }                                                                          \
};                                                                           \

BOOST_PP_REPEAT_FROM_TO(0, 9, MAKE_BIND_EXPR_GEN, _)

这很有效。但是，实现MakeBindExpr是否有一种不那么丑陋的方式？

以下是我现在能做的......如果你有兴趣知道......

//  N is arity
//  F is function type
//  FP is function pointer type
template < typename N, typename FP >
typename MakeBindExpr < N >::template result < FP >::type makeBindExpr(FP const & fp);

//  FP is a function pointer type 
template < typename FP >
void bind2Lua(char const * const fname, FP const & f)
{
  namespace ft = boost::function_types;
  using ft::function_type;
  using ft::function_arity;
  typedef function_type < FP >::type F;
  typedef function_arity < F >::type Arity;
  luabind::tag_function < F >(makeBindExpr < Arity::value >::template get(f));
}

deque < string >(string const &, string const &);
bind2Lua("names", getNames);