1[section boost/python/long.hpp] 2[section Introduction] 3Exposes a [link concepts.objectwrapper.typewrapper_concept_requirements TypeWrapper] for the Python [@http://www.python.org/doc/current/lib/typesnumeric.html long] integer type. 4[endsect] 5[section Class `long_`] 6Exposes the [@http://www.python.org/doc/current/lib/typesnumeric.html numeric type protocol] of Python's built-in `long` type. The semantics of the constructors and member functions defined below can be fully understood by reading the [link concepts.objectwrapper.typewrapper_concept_requirements TypeWrapper] concept definition. Since `long_` is publicly derived from [link object_wrappers.boost_python_object_hpp.class_object `object`], the public `object` interface applies to `long_` instances as well. 7`` 8namespace boost { namespace python 9{ 10 class long_ : public object 11 { 12 public: 13 long_(); // new long_ 14 15 template <class T> 16 explicit long_(T const& rhs); 17 18 template <class T, class U> 19 long_(T const& rhs, U const& base); 20 }; 21}} 22`` 23[endsect] 24[section Example] 25`` 26namespace python = boost::python; 27 28// compute a factorial without overflowing 29python::long_ fact(long n) 30{ 31 if (n == 0) 32 return python::long_(1); 33 else 34 return n * fact(n - 1); 35} 36`` 37[endsect] 38[endsect] 39