void replace(boost::ptr_vector<T>  &arg_ptr_vector, ///< The ptr_vector onto which the value should be pushed
		             const size_t          &idx,            ///< The index specifying the position to be replaced
					 std::unique_ptr<T>   &&arg_ptr_value   ///< The value to push_back, held by unique_ptr
					 ) {
			arg_ptr_vector.replace( idx, arg_ptr_value.release() );
		}