Random access to sequences

17 Aug 2005

      I read up on boost::mpl::at<...>. It's pretty cool, but I wanted to make it 
a little easier to use. I found it a little annoying to have to type out 
'int_<...>' for the index number, so I created a struct to automate that 
feature:

==========================
template<typename SEQ, int IDX>
struct atIdx
{
  typedef typename boost::mpl::at<SEQ, boost::mpl::int_<IDX> >::type type;
};
==========================

With the struct above, you can do the following:

=============================
typedef boost::mpl::vector<int, char, int> t;
atIdx<t, 0>::type i; // This line is shorter than the one below:
/* atIdx<t, boost::mpl::int_<0> >::type i; */
=============================

Is this feature already available in boost somewhere? If I've reinvented the 
wheel, I'll be happy to use an existing implementation...

Thanks,
--Steve

Stephen Gross
Case Western School of Medicine
Cleveland, OH

"By Grabthar's hammer, by the sons of Worvan, you shall be avenged." - Dr. 
Lazarus