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-rw-r--r--third_party/abseil_cpp/absl/random/exponential_distribution.h165
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diff --git a/third_party/abseil_cpp/absl/random/exponential_distribution.h b/third_party/abseil_cpp/absl/random/exponential_distribution.h
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index b5caf8a1e1f3..000000000000
--- a/third_party/abseil_cpp/absl/random/exponential_distribution.h
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@@ -1,165 +0,0 @@
-// Copyright 2017 The Abseil Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#ifndef ABSL_RANDOM_EXPONENTIAL_DISTRIBUTION_H_
-#define ABSL_RANDOM_EXPONENTIAL_DISTRIBUTION_H_
-
-#include <cassert>
-#include <cmath>
-#include <istream>
-#include <limits>
-#include <type_traits>
-
-#include "absl/meta/type_traits.h"
-#include "absl/random/internal/fast_uniform_bits.h"
-#include "absl/random/internal/generate_real.h"
-#include "absl/random/internal/iostream_state_saver.h"
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-
-// absl::exponential_distribution:
-// Generates a number conforming to an exponential distribution and is
-// equivalent to the standard [rand.dist.pois.exp] distribution.
-template <typename RealType = double>
-class exponential_distribution {
- public:
-  using result_type = RealType;
-
-  class param_type {
-   public:
-    using distribution_type = exponential_distribution;
-
-    explicit param_type(result_type lambda = 1) : lambda_(lambda) {
-      assert(lambda > 0);
-      neg_inv_lambda_ = -result_type(1) / lambda_;
-    }
-
-    result_type lambda() const { return lambda_; }
-
-    friend bool operator==(const param_type& a, const param_type& b) {
-      return a.lambda_ == b.lambda_;
-    }
-
-    friend bool operator!=(const param_type& a, const param_type& b) {
-      return !(a == b);
-    }
-
-   private:
-    friend class exponential_distribution;
-
-    result_type lambda_;
-    result_type neg_inv_lambda_;
-
-    static_assert(
-        std::is_floating_point<RealType>::value,
-        "Class-template absl::exponential_distribution<> must be parameterized "
-        "using a floating-point type.");
-  };
-
-  exponential_distribution() : exponential_distribution(1) {}
-
-  explicit exponential_distribution(result_type lambda) : param_(lambda) {}
-
-  explicit exponential_distribution(const param_type& p) : param_(p) {}
-
-  void reset() {}
-
-  // Generating functions
-  template <typename URBG>
-  result_type operator()(URBG& g) {  // NOLINT(runtime/references)
-    return (*this)(g, param_);
-  }
-
-  template <typename URBG>
-  result_type operator()(URBG& g,  // NOLINT(runtime/references)
-                         const param_type& p);
-
-  param_type param() const { return param_; }
-  void param(const param_type& p) { param_ = p; }
-
-  result_type(min)() const { return 0; }
-  result_type(max)() const {
-    return std::numeric_limits<result_type>::infinity();
-  }
-
-  result_type lambda() const { return param_.lambda(); }
-
-  friend bool operator==(const exponential_distribution& a,
-                         const exponential_distribution& b) {
-    return a.param_ == b.param_;
-  }
-  friend bool operator!=(const exponential_distribution& a,
-                         const exponential_distribution& b) {
-    return a.param_ != b.param_;
-  }
-
- private:
-  param_type param_;
-  random_internal::FastUniformBits<uint64_t> fast_u64_;
-};
-
-// --------------------------------------------------------------------------
-// Implementation details follow
-// --------------------------------------------------------------------------
-
-template <typename RealType>
-template <typename URBG>
-typename exponential_distribution<RealType>::result_type
-exponential_distribution<RealType>::operator()(
-    URBG& g,  // NOLINT(runtime/references)
-    const param_type& p) {
-  using random_internal::GenerateNegativeTag;
-  using random_internal::GenerateRealFromBits;
-  using real_type =
-      absl::conditional_t<std::is_same<RealType, float>::value, float, double>;
-
-  const result_type u = GenerateRealFromBits<real_type, GenerateNegativeTag,
-                                             false>(fast_u64_(g));  // U(-1, 0)
-
-  // log1p(-x) is mathematically equivalent to log(1 - x) but has more
-  // accuracy for x near zero.
-  return p.neg_inv_lambda_ * std::log1p(u);
-}
-
-template <typename CharT, typename Traits, typename RealType>
-std::basic_ostream<CharT, Traits>& operator<<(
-    std::basic_ostream<CharT, Traits>& os,  // NOLINT(runtime/references)
-    const exponential_distribution<RealType>& x) {
-  auto saver = random_internal::make_ostream_state_saver(os);
-  os.precision(random_internal::stream_precision_helper<RealType>::kPrecision);
-  os << x.lambda();
-  return os;
-}
-
-template <typename CharT, typename Traits, typename RealType>
-std::basic_istream<CharT, Traits>& operator>>(
-    std::basic_istream<CharT, Traits>& is,    // NOLINT(runtime/references)
-    exponential_distribution<RealType>& x) {  // NOLINT(runtime/references)
-  using result_type = typename exponential_distribution<RealType>::result_type;
-  using param_type = typename exponential_distribution<RealType>::param_type;
-  result_type lambda;
-
-  auto saver = random_internal::make_istream_state_saver(is);
-  lambda = random_internal::read_floating_point<result_type>(is);
-  if (!is.fail()) {
-    x.param(param_type(lambda));
-  }
-  return is;
-}
-
-ABSL_NAMESPACE_END
-}  // namespace absl
-
-#endif  // ABSL_RANDOM_EXPONENTIAL_DISTRIBUTION_H_