Re: Vectors of references

Larry Brunelle <lbrunelle@geotrace.com> wrote:


    references are not Copyable and Assigable only
that is
         int i,j;
         int &ir-i,&jr=j;
         jr = ir; //[1]
   is [1] is illegal in particular. To store 'references' in a vector
you need a reference_wrapper
a class containing a pointer the acts like a reference.

template <class T>
class ref_wrapper
{
     T *x;
  public:
      ref_wrapper(const T &a):x(&a){}
      operator T & () { return *x;{
      operator const T &() const {return *x;}
// what ever else i missed :)
};

std::vector<ref_wrapper<int> > data;
int i =1;
int j=2;

data.push_back(i);
data.push_back(j);

int &k = data.front() ;// k == 1 is true.

if I did not miss anything.
boost provides this and it it is easy to create a correct one ,or use
their tested code from www.boost.org.

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