[Boost-users] some questions regarding ref

From: abir basak (abirbasak_at_[hidden])
Date: 2007-02-03 05:29:48

Hi,
   I want to have a few classes to be stored inside a vector by 
reference. I thought to use boost::ref for that purpose , instead of 
storing pointer. However I am facing some problem regarding the operator & .

Here is a sample code which gives the problem,
struct T2{
        int x;	
        T2(int x) :x(x){}	
};
int main(int argc,char** argv) {
        std::vector<boost::reference_wrapper<T2> > v; /// vector stores 
reference, rather than value.
        T2 t1 = 10;
        T2 t2 = 15;
        v.push_back(boost::ref(t1)); /// push ref to t1.
        v.push_back(boost::ref(t2)); ///push ref to t2.
        v[0].get().x = 5;	///get by ref & change.
///        v[0].x = 5 ; this statement doesn't work!
        std::cout<<t1.x<<"\n"; ///change is reflected.
   return 0;
}
I am not sure why I have to use get for this purpose, while & operator 
is written for that purpose.
Using MSVC 7.1
Even I face problem like this,
struct T3{
        T2 t2_;
        T3(int x) : t2_(x){}
        T2& operator&(){
                return t2_;
        }
};
std::vector<T3> v3;
        v3.push_back(T3(4));
        v3.push_back(T3(5));
///         v3[0].x = 6; This doesn't work.
        (&v3[0]).x = 6; ///This works!
Can anyone say a little detail about the problem ?
-- 
Abir Basak, Member IEEE
Software Engineer, Read Ink Technologies
B. Tech, IIT Kharagpur
email: abir_at_[hidden]
homepage: www.abirbasak.com