constant references with typedef and templates in c++

Question

I heard the temporary objects can only be assigned to constant references.

But this code gives error

#include     
template

        

Answer 1

Your code gives error because the const qualifier in const ref error is just ignored because 8.3.2/1 says

Cv-qualified references are ill-formed except when the cv-qualifiers are introduced through the use of a typedef (7.1.3) or of a template type argument(14.3), in which case the cv-qualifiers are ignored.`

So error has type int& not const int& .