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- /* boost random/traits.hpp header file
- *
- * Copyright John Maddock 2015
- * Distributed under the Boost Software License, Version 1.0. (See
- * accompanying file LICENSE_1_0.txt or copy at
- * http://www.boost.org/LICENSE_1_0.txt)
- *
- * See http://www.boost.org for most recent version including documentation.
- *
- * These traits classes serve two purposes: they are designed to mostly
- * work out of the box for multiprecision types (ie number types that are
- * C++ class types and not integers or floats from type-traits point of view),
- * they are also a potential point of specialization for user-defined
- * number types.
- *
- * $Id$
- */
- #ifndef BOOST_RANDOM_TRAITS_HPP
- #define BOOST_RANDOM_TRAITS_HPP
- #include <boost/type_traits/is_signed.hpp>
- #include <boost/type_traits/is_integral.hpp>
- #include <boost/type_traits/make_unsigned.hpp>
- #include <boost/mpl/bool.hpp>
- #include <limits>
- namespace boost {
- namespace random {
- namespace traits {
- // \cond show_private
- template <class T, bool intrinsic>
- struct make_unsigned_imp
- {
- typedef typename boost::make_unsigned<T>::type type;
- };
- template <class T>
- struct make_unsigned_imp<T, false>
- {
- BOOST_STATIC_ASSERT(std::numeric_limits<T>::is_specialized);
- BOOST_STATIC_ASSERT(std::numeric_limits<T>::is_signed == false);
- BOOST_STATIC_ASSERT(std::numeric_limits<T>::is_integer == true);
- typedef T type;
- };
- // \endcond
- /** \brief Converts the argument type T to an unsigned type.
- *
- * This trait has a single member `type` which is the unsigned type corresponding to T.
- * Note that
- * if T is signed, then member `type` *should define a type with one more bit precision than T*. For built-in
- * types this trait defaults to `boost::make_unsigned<T>::type`. For user defined types it simply asserts that
- * the argument type T is an unsigned integer (using std::numeric_limits).
- * User defined specializations may be provided for other cases.
- */
- template <class T>
- struct make_unsigned
- // \cond show_private
- : public make_unsigned_imp < T, boost::is_integral<T>::value >
- // \endcond
- {};
- // \cond show_private
- template <class T, bool intrinsic>
- struct make_unsigned_or_unbounded_imp
- {
- typedef typename boost::make_unsigned<T>::type type;
- };
- template <class T>
- struct make_unsigned_or_unbounded_imp<T, false>
- {
- BOOST_STATIC_ASSERT(std::numeric_limits<T>::is_specialized);
- BOOST_STATIC_ASSERT((std::numeric_limits<T>::is_signed == false) || (std::numeric_limits<T>::is_bounded == false));
- BOOST_STATIC_ASSERT(std::numeric_limits<T>::is_integer == true);
- typedef T type;
- };
- // \endcond
- /** \brief Converts the argument type T to either an unsigned type or an unbounded integer type.
- *
- * This trait has a single member `type` which is either the unsigned type corresponding to T or an unbounded
- * integer type. This trait is used to generate types suitable for the calculation of a range: as a result
- * if T is signed, then member `type` *should define a type with one more bit precision than T*. For built-in
- * types this trait defaults to `boost::make_unsigned<T>::type`. For user defined types it simply asserts that
- * the argument type T is either an unbounded integer, or an unsigned one (using std::numeric_limits).
- * User defined specializations may be provided for other cases.
- */
- template <class T>
- struct make_unsigned_or_unbounded
- // \cond show_private
- : public make_unsigned_or_unbounded_imp < T, boost::is_integral<T>::value >
- // \endcond
- {};
- /** \brief Traits class that indicates whether type T is an integer
- */
- template <class T>
- struct is_integral
- : public mpl::bool_<boost::is_integral<T>::value || (std::numeric_limits<T>::is_integer)>
- {};
- /** \brief Traits class that indicates whether type T is a signed integer
- */
- template <class T> struct is_signed
- : public mpl::bool_ < boost::is_signed<T>::value || (std::numeric_limits<T>::is_specialized && std::numeric_limits<T>::is_integer && std::numeric_limits<T>::is_signed)>
- {};
- }
- }
- }
- #endif
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