epoc32/include/stdapis/boost/random/xor_combine.hpp
author William Roberts <williamr@symbian.org>
Wed, 31 Mar 2010 12:33:34 +0100
branchSymbian3
changeset 4 837f303aceeb
permissions -rw-r--r--
Current Symbian^3 public API header files (from PDK 3.0.h)
This is the epoc32/include tree with the "platform" subtrees removed, and
all but a selected few mbg and rsg files removed.
     1 /* boost random/xor_combine.hpp header file
     2  *
     3  * Copyright Jens Maurer 2002
     4  * Distributed under the Boost Software License, Version 1.0. (See
     5  * accompanying file LICENSE_1_0.txt or copy at
     6  * http://www.boost.org/LICENSE_1_0.txt)
     7  *
     8  * See http://www.boost.org for most recent version including documentation.
     9  *
    10  * $Id: xor_combine.hpp,v 1.13 2005/05/21 15:57:00 dgregor Exp $
    11  *
    12  */
    13 
    14 #ifndef BOOST_RANDOM_XOR_COMBINE_HPP
    15 #define BOOST_RANDOM_XOR_COMBINE_HPP
    16 
    17 #include <iostream>
    18 #include <cassert>
    19 #include <algorithm> // for std::min and std::max
    20 #include <boost/config.hpp>
    21 #include <boost/limits.hpp>
    22 #include <boost/static_assert.hpp>
    23 #include <boost/cstdint.hpp>     // uint32_t
    24 
    25 
    26 namespace boost {
    27 namespace random {
    28 
    29 template<class URNG1, int s1, class URNG2, int s2,
    30 #ifndef BOOST_NO_DEPENDENT_TYPES_IN_TEMPLATE_VALUE_PARAMETERS
    31   typename URNG1::result_type 
    32 #else
    33   uint32_t
    34 #endif
    35   val = 0>
    36 class xor_combine
    37 {
    38 public:
    39   typedef URNG1 base1_type;
    40   typedef URNG2 base2_type;
    41   typedef typename base1_type::result_type result_type;
    42 
    43   BOOST_STATIC_CONSTANT(bool, has_fixed_range = false);
    44   BOOST_STATIC_CONSTANT(int, shift1 = s1);
    45   BOOST_STATIC_CONSTANT(int, shfit2 = s2);
    46 
    47   xor_combine() : _rng1(), _rng2()
    48   { }
    49   xor_combine(const base1_type & rng1, const base2_type & rng2)
    50     : _rng1(rng1), _rng2(rng2) { }
    51   template<class It> xor_combine(It& first, It last)
    52     : _rng1(first, last), _rng2( /* advanced by other call */ first, last) { }
    53   void seed() { _rng1.seed(); _rng2.seed(); }
    54   template<class It> void seed(It& first, It last)
    55   {
    56     _rng1.seed(first, last);
    57     _rng2.seed(first, last);
    58   }
    59 
    60   const base1_type& base1() { return _rng1; }
    61   const base2_type& base2() { return _rng2; }
    62 
    63   result_type operator()()
    64   {
    65     // MSVC fails BOOST_STATIC_ASSERT with std::numeric_limits at class scope
    66 #if !defined(BOOST_NO_LIMITS_COMPILE_TIME_CONSTANTS) && !(defined(BOOST_MSVC) && BOOST_MSVC <= 1300)
    67     BOOST_STATIC_ASSERT(std::numeric_limits<typename base1_type::result_type>::is_integer);
    68     BOOST_STATIC_ASSERT(std::numeric_limits<typename base2_type::result_type>::is_integer);
    69     BOOST_STATIC_ASSERT(std::numeric_limits<typename base1_type::result_type>::digits >= std::numeric_limits<typename base2_type::result_type>::digits);
    70 #endif
    71     return (_rng1() << s1) ^ (_rng2() << s2);
    72   }
    73 
    74   result_type min BOOST_PREVENT_MACRO_SUBSTITUTION () const { return std::min BOOST_PREVENT_MACRO_SUBSTITUTION((_rng1.min)(), (_rng2.min)()); }
    75   result_type max BOOST_PREVENT_MACRO_SUBSTITUTION () const { return std::max BOOST_PREVENT_MACRO_SUBSTITUTION((_rng1.min)(), (_rng2.max)()); }
    76   static bool validation(result_type x) { return val == x; }
    77 
    78 #ifndef BOOST_NO_OPERATORS_IN_NAMESPACE
    79 
    80 #ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
    81   template<class CharT, class Traits>
    82   friend std::basic_ostream<CharT,Traits>&
    83   operator<<(std::basic_ostream<CharT,Traits>& os, const xor_combine& s)
    84   {
    85     os << s._rng1 << " " << s._rng2 << " ";
    86     return os;
    87   }
    88 
    89   template<class CharT, class Traits>
    90   friend std::basic_istream<CharT,Traits>&
    91   operator>>(std::basic_istream<CharT,Traits>& is, xor_combine& s)
    92   {
    93     is >> s._rng1 >> std::ws >> s._rng2 >> std::ws;
    94     return is;
    95   }
    96 #endif
    97 
    98   friend bool operator==(const xor_combine& x, const xor_combine& y)
    99   { return x._rng1 == y._rng1 && x._rng2 == y._rng2; }
   100   friend bool operator!=(const xor_combine& x, const xor_combine& y)
   101   { return !(x == y); }
   102 #else
   103   // Use a member function; Streamable concept not supported.
   104   bool operator==(const xor_combine& rhs) const
   105   { return _rng1 == rhs._rng1 && _rng2 == rhs._rng2; }
   106   bool operator!=(const xor_combine& rhs) const
   107   { return !(*this == rhs); }
   108 #endif
   109 
   110 private:
   111   base1_type _rng1;
   112   base2_type _rng2;
   113 };
   114 
   115 #ifndef BOOST_NO_INCLASS_MEMBER_INITIALIZATION
   116 //  A definition is required even for integral static constants
   117 template<class URNG1, int s1, class URNG2, int s2,
   118 #ifndef BOOST_NO_DEPENDENT_TYPES_IN_TEMPLATE_VALUE_PARAMETERS
   119   typename URNG1::result_type 
   120 #else
   121   uint32_t
   122 #endif
   123   val>
   124 const bool xor_combine<URNG1, s1, URNG2, s2, val>::has_fixed_range;
   125 #endif
   126 
   127 } // namespace random
   128 } // namespace boost
   129 
   130 #endif // BOOST_RANDOM_XOR_COMBINE_HPP