Although uniform_smallint_integer currently is no official code (its in the details section and seems nowhere used), I would like to mention, that the current implementation contains a subtle bug: The member _factor is never initialized, thus calling operator()() would cause U.B. The reason is, that the initializer member function set defines a **local** variable _factor, which is never assigned to this->_factor, such that uniform_smallint_integer::_factor will never be assigned. Just one question: Is detail::uniform_smallint_integer a leftover of some experiments by the library responsible or does it exist for interested boost users to test it? Greetings from Bremen, Daniel