Trying to copy a unique_ptr

unique_ptr_fail1.cpp

#include <memory>

class A
{
public:
    A( std::unique_ptr< int > v ) : m_v( v ) {}

    std::unique_ptr< int > m_v;
};

int main( int argc, char** argv )
{
    std::unique_ptr< int > i( new int(10) );
    A a( i );
}