Hi Max & Ravi

Ravi wrote: 
On Saturday 03 May 2008 09:12:01 pm Max wrote:
  
     double d0, d1, d2, d3;
     boost::array<double &, 4> array = {{d0, d1, d2, d3}};
     for(int i=0; i<4; i++) array[i] = i;
     assert(d2 == 2);
        

[snip]

  
If it won't take a long time, is it possible to rewrite the above code
snnipet making use of boost.Ref?
    

#include <boost/array.hpp>
#include <boost/ref.hpp>

#include <cassert>

int main()
{
  typedef boost::reference_wrapper<double> double_ref_t;
  boost::array<double, 2> array;

  double_ref_t d0( array[0] );
  double_ref_t d1( array[1] );

  array[0] = 1.0;
  array[1] = 2.0;
  assert( d1 == 2.0 );

  d0 += d1;
  assert( d0 == 3.0 );
}
or even:

#include <cassert>
#include <boost/array.hpp>
#include <boost/ref.hpp>

int main()
{
    double d0, d1, d2, d3;
    boost::array<boost::reference_wrapper<double>, 4> array = {boost::ref(d0), boost::ref(d1), boost::ref(d2), boost::ref(d3)};
    for(int i=0; i<4; i++)
    {
        array[i].get() = i;
    }
    assert(d2 == 2);

    return 0;
}

although this is a slightly unusual construct which might suffer nasty aliasing issues, perhaps a few more details of your requirement might clarify a better approach.
-- 
Bill Somerville
Class Design Limited