108 lines
4.2 KiB
Plaintext
108 lines
4.2 KiB
Plaintext
/* 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
|