1*38fd1498Szrj// <experimental/random> -*- C++ -*- 2*38fd1498Szrj 3*38fd1498Szrj// Copyright (C) 2015-2018 Free Software Foundation, Inc. 4*38fd1498Szrj// 5*38fd1498Szrj// This file is part of the GNU ISO C++ Library. This library is free 6*38fd1498Szrj// software; you can redistribute it and/or modify it under the 7*38fd1498Szrj// terms of the GNU General Public License as published by the 8*38fd1498Szrj// Free Software Foundation; either version 3, or (at your option) 9*38fd1498Szrj// any later version. 10*38fd1498Szrj 11*38fd1498Szrj// This library is distributed in the hope that it will be useful, 12*38fd1498Szrj// but WITHOUT ANY WARRANTY; without even the implied warranty of 13*38fd1498Szrj// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14*38fd1498Szrj// GNU General Public License for more details. 15*38fd1498Szrj 16*38fd1498Szrj// Under Section 7 of GPL version 3, you are granted additional 17*38fd1498Szrj// permissions described in the GCC Runtime Library Exception, version 18*38fd1498Szrj// 3.1, as published by the Free Software Foundation. 19*38fd1498Szrj 20*38fd1498Szrj// You should have received a copy of the GNU General Public License and 21*38fd1498Szrj// a copy of the GCC Runtime Library Exception along with this program; 22*38fd1498Szrj// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23*38fd1498Szrj// <http://www.gnu.org/licenses/>. 24*38fd1498Szrj 25*38fd1498Szrj/** @file experimental/random 26*38fd1498Szrj * This is a TS C++ Library header. 27*38fd1498Szrj */ 28*38fd1498Szrj 29*38fd1498Szrj#ifndef _GLIBCXX_EXPERIMENTAL_RANDOM 30*38fd1498Szrj#define _GLIBCXX_EXPERIMENTAL_RANDOM 1 31*38fd1498Szrj 32*38fd1498Szrj#include <random> 33*38fd1498Szrj#include <experimental/bits/lfts_config.h> 34*38fd1498Szrj 35*38fd1498Szrjnamespace std { 36*38fd1498Szrj_GLIBCXX_BEGIN_NAMESPACE_VERSION 37*38fd1498Szrj 38*38fd1498Szrjnamespace experimental { 39*38fd1498Szrjinline namespace fundamentals_v2 { 40*38fd1498Szrj#define __cpp_lib_experimental_randint 201511 41*38fd1498Szrj 42*38fd1498Szrj inline std::default_random_engine& 43*38fd1498Szrj _S_randint_engine() 44*38fd1498Szrj { 45*38fd1498Szrj static thread_local default_random_engine __eng{random_device{}()}; 46*38fd1498Szrj return __eng; 47*38fd1498Szrj } 48*38fd1498Szrj 49*38fd1498Szrj // 13.2.2.1, Function template randint 50*38fd1498Szrj template<typename _IntType> 51*38fd1498Szrj inline _IntType 52*38fd1498Szrj randint(_IntType __a, _IntType __b) 53*38fd1498Szrj { 54*38fd1498Szrj static_assert(is_integral<_IntType>::value && sizeof(_IntType) > 1, 55*38fd1498Szrj "argument must be an integer type"); 56*38fd1498Szrj using _Dist = std::uniform_int_distribution<_IntType>; 57*38fd1498Szrj // This relies on the fact our uniform_int_distribution is stateless, 58*38fd1498Szrj // otherwise we'd need a static thread_local _Dist and pass it 59*38fd1498Szrj // _Dist::param_type{__a, __b}. 60*38fd1498Szrj return _Dist(__a, __b)(_S_randint_engine()); 61*38fd1498Szrj } 62*38fd1498Szrj 63*38fd1498Szrj inline void 64*38fd1498Szrj reseed() 65*38fd1498Szrj { 66*38fd1498Szrj _S_randint_engine().seed(random_device{}()); 67*38fd1498Szrj } 68*38fd1498Szrj 69*38fd1498Szrj inline void 70*38fd1498Szrj reseed(default_random_engine::result_type __value) 71*38fd1498Szrj { 72*38fd1498Szrj _S_randint_engine().seed(__value); 73*38fd1498Szrj } 74*38fd1498Szrj} // namespace fundamentals_v2 75*38fd1498Szrj} // namespace experimental 76*38fd1498Szrj 77*38fd1498Szrj_GLIBCXX_END_NAMESPACE_VERSION 78*38fd1498Szrj} // namespace std 79*38fd1498Szrj 80*38fd1498Szrj#endif 81