/*
namespace My
{
	class Description {};
	class WaterTable {};
	class GPM {};
	class IsRunning {};
}

typedef CSV::Entry<
   My::Description, std::string,   CSV::Entry<
   My::WaterTable,  int,           CSV::Entry<
   My::GPM,         float,         CSV::Entry<
   My::IsRunning,   bool,          CSV::eol> > >
> My_CSVType;

if(!CSV::Field<My_CSVType,My::Description>::IsNull(tt)) {
   std::string test = CSV::Field<My_CSVType,My::Description>::Data(tt);
   std::cout << test << std::endl;
} else {
   std::cout << "NULL" << std::endl;
}

.\Visual Studio Projects\csvtest\csvtest.cpp(77) : error C2440: 'initializing' : cannot convert from 'int' to 'std::basic_string<_Elem,_Traits,_Ax>'
        with
        [
            _Elem=char,
            _Traits=std::char_traits<char>,
            _Ax=std::allocator<char>
        ]
        No constructor could take the source type, or constructor overload resolution was ambiguous
 */

///
/// CSVField
///

template< typename T1 >
struct is_same_part_1
{
    template<typename T2>  struct part_2     { enum { value = false }; };
    template<>             struct part_2<T1> { enum { value = true }; };
};
template< typename T1, typename T2 >
struct is_same_impl
{
    enum { value = is_same_part_1<T1>::template part_2<T2>::value };
};

template < typename TypeList, typename FIELD, bool isField = is_same_impl<FIELD,TypeList::FieldName>::value >
struct Field {
	static /*unspecified*/ Data(TypeList& tt);
	static bool IsNull(TypeList& tt);
};
template < typename TypeList, typename FIELD >
struct Field<TypeList,FIELD,false>
{
	static /*unspecified*/ Data(TypeList& tt) { return Field<TypeList::NextType, FIELD>::Data(tt.Next); }
	static bool IsNull(TypeList& tt) { return Field<TypeList::NextType, FIELD>::IsNull(tt.Next); }
};
template < typename TypeList, typename FIELD >
struct Field<TypeList,FIELD,true>
{
	static /*unspecified*/ Data(TypeList& tt) { return tt.Data; }
	static bool IsNull(TypeList& tt) { return tt.IsNull; }
};

///
/// CSVField_n
///

template < typename TypeList, unsigned FIELD >
struct Field_n
{
	static /*unspecified*/ Data(TypeList& tt) { return Field_n<TypeList::NextType,FIELD-1>::Data(tt.Next); }
	static bool IsNull(TypeList& tt) { return Field_n<TypeList::NextType,FIELD-1>::IsNull(tt.Next); }
};
template< typename TypeList >
struct Field_n<TypeList,0>
{
	static /*unspecified*/ Data(TypeList& tt) { return tt.Data; }
	static bool IsNull(TypeList& tt) { return tt.IsNull; }
};