[boost] [TypeErasure] assignment operator of any references

Subject: [boost] [TypeErasure] assignment operator of any references
From: Vicente J. Botet Escriba (vicente.botet_at_[hidden])
Date: 2012-07-18 17:15:20

Hi,

The References section constains this example:

int  i,  j;
any<typeid_<>,  _self&>  x(i),  y(j);
x  =  y;  // error

The following basic c++ code

int i=1, j=0;
int& x(i);
int& y(j);
x = y; // [1]

works and the expected value of x after [1] is 0.

Which concept requirements should I add to make the following work? 
assignable?

int  i,  j;
any<mpl::vector<typeid_<>, ...>,  _self&>  x(i),  y(j);
x  =  y;  // no error

Best,
Vicente