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authorDaniel Friesel <daniel.friesel@uos.de>2020-09-07 12:57:04 +0200
committerDaniel Friesel <daniel.friesel@uos.de>2020-09-07 12:57:04 +0200
commit0558244645611f314f47e0fa427f7323ce253eaf (patch)
tree824bcd55ec8577703345106d0a08e167407500a7 /include/lib/modernjson/detail/conversions
parent0248c6352f2117e50fac71dd632a79d8fa4f8737 (diff)
remove external libraries from main branch
Diffstat (limited to 'include/lib/modernjson/detail/conversions')
-rw-r--r--include/lib/modernjson/detail/conversions/from_json.hpp370
-rw-r--r--include/lib/modernjson/detail/conversions/to_chars.hpp1094
-rw-r--r--include/lib/modernjson/detail/conversions/to_json.hpp342
3 files changed, 0 insertions, 1806 deletions
diff --git a/include/lib/modernjson/detail/conversions/from_json.hpp b/include/lib/modernjson/detail/conversions/from_json.hpp
deleted file mode 100644
index 817d4b7..0000000
--- a/include/lib/modernjson/detail/conversions/from_json.hpp
+++ /dev/null
@@ -1,370 +0,0 @@
-#pragma once
-
-#include <algorithm> // transform
-#include <array> // array
-#include <ciso646> // and, not
-#include <forward_list> // forward_list
-#include <iterator> // inserter, front_inserter, end
-#include <map> // map
-#include <string> // string
-#include <tuple> // tuple, make_tuple
-#include <type_traits> // is_arithmetic, is_same, is_enum, underlying_type, is_convertible
-#include <unordered_map> // unordered_map
-#include <utility> // pair, declval
-#include <valarray> // valarray
-
-#include <lib/modernjson/detail/exceptions.hpp>
-#include <lib/modernjson/detail/macro_scope.hpp>
-#include <lib/modernjson/detail/meta/cpp_future.hpp>
-#include <lib/modernjson/detail/meta/type_traits.hpp>
-#include <lib/modernjson/detail/value_t.hpp>
-
-namespace nlohmann
-{
-namespace detail
-{
-template<typename BasicJsonType>
-void from_json(const BasicJsonType& j, typename std::nullptr_t& n)
-{
- if (JSON_UNLIKELY(not j.is_null()))
- {
- JSON_THROW(type_error::create(302, "type must be null, but is " + std::string(j.type_name())));
- }
- n = nullptr;
-}
-
-// overloads for basic_json template parameters
-template<typename BasicJsonType, typename ArithmeticType,
- enable_if_t<std::is_arithmetic<ArithmeticType>::value and
- not std::is_same<ArithmeticType, typename BasicJsonType::boolean_t>::value,
- int> = 0>
-void get_arithmetic_value(const BasicJsonType& j, ArithmeticType& val)
-{
- switch (static_cast<value_t>(j))
- {
- case value_t::number_unsigned:
- {
- val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_unsigned_t*>());
- break;
- }
- case value_t::number_integer:
- {
- val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_integer_t*>());
- break;
- }
- case value_t::number_float:
- {
- val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_float_t*>());
- break;
- }
-
- default:
- JSON_THROW(type_error::create(302, "type must be number, but is " + std::string(j.type_name())));
- }
-}
-
-template<typename BasicJsonType>
-void from_json(const BasicJsonType& j, typename BasicJsonType::boolean_t& b)
-{
- if (JSON_UNLIKELY(not j.is_boolean()))
- {
- JSON_THROW(type_error::create(302, "type must be boolean, but is " + std::string(j.type_name())));
- }
- b = *j.template get_ptr<const typename BasicJsonType::boolean_t*>();
-}
-
-template<typename BasicJsonType>
-void from_json(const BasicJsonType& j, typename BasicJsonType::string_t& s)
-{
- if (JSON_UNLIKELY(not j.is_string()))
- {
- JSON_THROW(type_error::create(302, "type must be string, but is " + std::string(j.type_name())));
- }
- s = *j.template get_ptr<const typename BasicJsonType::string_t*>();
-}
-
-template <
- typename BasicJsonType, typename ConstructibleStringType,
- enable_if_t <
- is_constructible_string_type<BasicJsonType, ConstructibleStringType>::value and
- not std::is_same<typename BasicJsonType::string_t,
- ConstructibleStringType>::value,
- int > = 0 >
-void from_json(const BasicJsonType& j, ConstructibleStringType& s)
-{
- if (JSON_UNLIKELY(not j.is_string()))
- {
- JSON_THROW(type_error::create(302, "type must be string, but is " + std::string(j.type_name())));
- }
-
- s = *j.template get_ptr<const typename BasicJsonType::string_t*>();
-}
-
-template<typename BasicJsonType>
-void from_json(const BasicJsonType& j, typename BasicJsonType::number_float_t& val)
-{
- get_arithmetic_value(j, val);
-}
-
-template<typename BasicJsonType>
-void from_json(const BasicJsonType& j, typename BasicJsonType::number_unsigned_t& val)
-{
- get_arithmetic_value(j, val);
-}
-
-template<typename BasicJsonType>
-void from_json(const BasicJsonType& j, typename BasicJsonType::number_integer_t& val)
-{
- get_arithmetic_value(j, val);
-}
-
-template<typename BasicJsonType, typename EnumType,
- enable_if_t<std::is_enum<EnumType>::value, int> = 0>
-void from_json(const BasicJsonType& j, EnumType& e)
-{
- typename std::underlying_type<EnumType>::type val;
- get_arithmetic_value(j, val);
- e = static_cast<EnumType>(val);
-}
-
-// forward_list doesn't have an insert method
-template<typename BasicJsonType, typename T, typename Allocator,
- enable_if_t<std::is_convertible<BasicJsonType, T>::value, int> = 0>
-void from_json(const BasicJsonType& j, std::forward_list<T, Allocator>& l)
-{
- if (JSON_UNLIKELY(not j.is_array()))
- {
- JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name())));
- }
- std::transform(j.rbegin(), j.rend(),
- std::front_inserter(l), [](const BasicJsonType & i)
- {
- return i.template get<T>();
- });
-}
-
-// valarray doesn't have an insert method
-template<typename BasicJsonType, typename T,
- enable_if_t<std::is_convertible<BasicJsonType, T>::value, int> = 0>
-void from_json(const BasicJsonType& j, std::valarray<T>& l)
-{
- if (JSON_UNLIKELY(not j.is_array()))
- {
- JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name())));
- }
- l.resize(j.size());
- std::copy(j.m_value.array->begin(), j.m_value.array->end(), std::begin(l));
-}
-
-template<typename BasicJsonType>
-void from_json_array_impl(const BasicJsonType& j, typename BasicJsonType::array_t& arr, priority_tag<3> /*unused*/)
-{
- arr = *j.template get_ptr<const typename BasicJsonType::array_t*>();
-}
-
-template <typename BasicJsonType, typename T, std::size_t N>
-auto from_json_array_impl(const BasicJsonType& j, std::array<T, N>& arr,
- priority_tag<2> /*unused*/)
--> decltype(j.template get<T>(), void())
-{
- for (std::size_t i = 0; i < N; ++i)
- {
- arr[i] = j.at(i).template get<T>();
- }
-}
-
-template<typename BasicJsonType, typename ConstructibleArrayType>
-auto from_json_array_impl(const BasicJsonType& j, ConstructibleArrayType& arr, priority_tag<1> /*unused*/)
--> decltype(
- arr.reserve(std::declval<typename ConstructibleArrayType::size_type>()),
- j.template get<typename ConstructibleArrayType::value_type>(),
- void())
-{
- using std::end;
-
- arr.reserve(j.size());
- std::transform(j.begin(), j.end(),
- std::inserter(arr, end(arr)), [](const BasicJsonType & i)
- {
- // get<BasicJsonType>() returns *this, this won't call a from_json
- // method when value_type is BasicJsonType
- return i.template get<typename ConstructibleArrayType::value_type>();
- });
-}
-
-template <typename BasicJsonType, typename ConstructibleArrayType>
-void from_json_array_impl(const BasicJsonType& j, ConstructibleArrayType& arr,
- priority_tag<0> /*unused*/)
-{
- using std::end;
-
- std::transform(
- j.begin(), j.end(), std::inserter(arr, end(arr)),
- [](const BasicJsonType & i)
- {
- // get<BasicJsonType>() returns *this, this won't call a from_json
- // method when value_type is BasicJsonType
- return i.template get<typename ConstructibleArrayType::value_type>();
- });
-}
-
-template <typename BasicJsonType, typename ConstructibleArrayType,
- enable_if_t <
- is_constructible_array_type<BasicJsonType, ConstructibleArrayType>::value and
- not is_constructible_object_type<BasicJsonType, ConstructibleArrayType>::value and
- not is_constructible_string_type<BasicJsonType, ConstructibleArrayType>::value and
- not is_basic_json<ConstructibleArrayType>::value,
- int > = 0 >
-
-auto from_json(const BasicJsonType& j, ConstructibleArrayType& arr)
--> decltype(from_json_array_impl(j, arr, priority_tag<3> {}),
-j.template get<typename ConstructibleArrayType::value_type>(),
-void())
-{
- if (JSON_UNLIKELY(not j.is_array()))
- {
- JSON_THROW(type_error::create(302, "type must be array, but is " +
- std::string(j.type_name())));
- }
-
- from_json_array_impl(j, arr, priority_tag<3> {});
-}
-
-template<typename BasicJsonType, typename ConstructibleObjectType,
- enable_if_t<is_constructible_object_type<BasicJsonType, ConstructibleObjectType>::value, int> = 0>
-void from_json(const BasicJsonType& j, ConstructibleObjectType& obj)
-{
- if (JSON_UNLIKELY(not j.is_object()))
- {
- JSON_THROW(type_error::create(302, "type must be object, but is " + std::string(j.type_name())));
- }
-
- auto inner_object = j.template get_ptr<const typename BasicJsonType::object_t*>();
- using value_type = typename ConstructibleObjectType::value_type;
- std::transform(
- inner_object->begin(), inner_object->end(),
- std::inserter(obj, obj.begin()),
- [](typename BasicJsonType::object_t::value_type const & p)
- {
- return value_type(p.first, p.second.template get<typename ConstructibleObjectType::mapped_type>());
- });
-}
-
-// overload for arithmetic types, not chosen for basic_json template arguments
-// (BooleanType, etc..); note: Is it really necessary to provide explicit
-// overloads for boolean_t etc. in case of a custom BooleanType which is not
-// an arithmetic type?
-template<typename BasicJsonType, typename ArithmeticType,
- enable_if_t <
- std::is_arithmetic<ArithmeticType>::value and
- not std::is_same<ArithmeticType, typename BasicJsonType::number_unsigned_t>::value and
- not std::is_same<ArithmeticType, typename BasicJsonType::number_integer_t>::value and
- not std::is_same<ArithmeticType, typename BasicJsonType::number_float_t>::value and
- not std::is_same<ArithmeticType, typename BasicJsonType::boolean_t>::value,
- int> = 0>
-void from_json(const BasicJsonType& j, ArithmeticType& val)
-{
- switch (static_cast<value_t>(j))
- {
- case value_t::number_unsigned:
- {
- val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_unsigned_t*>());
- break;
- }
- case value_t::number_integer:
- {
- val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_integer_t*>());
- break;
- }
- case value_t::number_float:
- {
- val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_float_t*>());
- break;
- }
- case value_t::boolean:
- {
- val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::boolean_t*>());
- break;
- }
-
- default:
- JSON_THROW(type_error::create(302, "type must be number, but is " + std::string(j.type_name())));
- }
-}
-
-template<typename BasicJsonType, typename A1, typename A2>
-void from_json(const BasicJsonType& j, std::pair<A1, A2>& p)
-{
- p = {j.at(0).template get<A1>(), j.at(1).template get<A2>()};
-}
-
-template<typename BasicJsonType, typename Tuple, std::size_t... Idx>
-void from_json_tuple_impl(const BasicJsonType& j, Tuple& t, index_sequence<Idx...> /*unused*/)
-{
- t = std::make_tuple(j.at(Idx).template get<typename std::tuple_element<Idx, Tuple>::type>()...);
-}
-
-template<typename BasicJsonType, typename... Args>
-void from_json(const BasicJsonType& j, std::tuple<Args...>& t)
-{
- from_json_tuple_impl(j, t, index_sequence_for<Args...> {});
-}
-
-template <typename BasicJsonType, typename Key, typename Value, typename Compare, typename Allocator,
- typename = enable_if_t<not std::is_constructible<
- typename BasicJsonType::string_t, Key>::value>>
-void from_json(const BasicJsonType& j, std::map<Key, Value, Compare, Allocator>& m)
-{
- if (JSON_UNLIKELY(not j.is_array()))
- {
- JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name())));
- }
- for (const auto& p : j)
- {
- if (JSON_UNLIKELY(not p.is_array()))
- {
- JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(p.type_name())));
- }
- m.emplace(p.at(0).template get<Key>(), p.at(1).template get<Value>());
- }
-}
-
-template <typename BasicJsonType, typename Key, typename Value, typename Hash, typename KeyEqual, typename Allocator,
- typename = enable_if_t<not std::is_constructible<
- typename BasicJsonType::string_t, Key>::value>>
-void from_json(const BasicJsonType& j, std::unordered_map<Key, Value, Hash, KeyEqual, Allocator>& m)
-{
- if (JSON_UNLIKELY(not j.is_array()))
- {
- JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name())));
- }
- for (const auto& p : j)
- {
- if (JSON_UNLIKELY(not p.is_array()))
- {
- JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(p.type_name())));
- }
- m.emplace(p.at(0).template get<Key>(), p.at(1).template get<Value>());
- }
-}
-
-struct from_json_fn
-{
- template<typename BasicJsonType, typename T>
- auto operator()(const BasicJsonType& j, T& val) const
- noexcept(noexcept(from_json(j, val)))
- -> decltype(from_json(j, val), void())
- {
- return from_json(j, val);
- }
-};
-} // namespace detail
-
-/// namespace to hold default `from_json` function
-/// to see why this is required:
-/// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4381.html
-namespace
-{
-constexpr const auto& from_json = detail::static_const<detail::from_json_fn>::value;
-} // namespace
-} // namespace nlohmann
diff --git a/include/lib/modernjson/detail/conversions/to_chars.hpp b/include/lib/modernjson/detail/conversions/to_chars.hpp
deleted file mode 100644
index b32e176..0000000
--- a/include/lib/modernjson/detail/conversions/to_chars.hpp
+++ /dev/null
@@ -1,1094 +0,0 @@
-#pragma once
-
-#include <cassert> // assert
-#include <ciso646> // or, and, not
-#include <cmath> // signbit, isfinite
-#include <cstdint> // intN_t, uintN_t
-#include <cstring> // memcpy, memmove
-
-namespace nlohmann
-{
-namespace detail
-{
-
-/*!
-@brief implements the Grisu2 algorithm for binary to decimal floating-point
-conversion.
-
-This implementation is a slightly modified version of the reference
-implementation which may be obtained from
-http://florian.loitsch.com/publications (bench.tar.gz).
-
-The code is distributed under the MIT license, Copyright (c) 2009 Florian Loitsch.
-
-For a detailed description of the algorithm see:
-
-[1] Loitsch, "Printing Floating-Point Numbers Quickly and Accurately with
- Integers", Proceedings of the ACM SIGPLAN 2010 Conference on Programming
- Language Design and Implementation, PLDI 2010
-[2] Burger, Dybvig, "Printing Floating-Point Numbers Quickly and Accurately",
- Proceedings of the ACM SIGPLAN 1996 Conference on Programming Language
- Design and Implementation, PLDI 1996
-*/
-namespace dtoa_impl
-{
-
-template <typename Target, typename Source>
-Target reinterpret_bits(const Source source)
-{
- static_assert(sizeof(Target) == sizeof(Source), "size mismatch");
-
- Target target;
- std::memcpy(&target, &source, sizeof(Source));
- return target;
-}
-
-struct diyfp // f * 2^e
-{
- static constexpr int kPrecision = 64; // = q
-
- uint64_t f = 0;
- int e = 0;
-
- constexpr diyfp(uint64_t f_, int e_) noexcept : f(f_), e(e_) {}
-
- /*!
- @brief returns x - y
- @pre x.e == y.e and x.f >= y.f
- */
- static diyfp sub(const diyfp& x, const diyfp& y) noexcept
- {
- assert(x.e == y.e);
- assert(x.f >= y.f);
-
- return {x.f - y.f, x.e};
- }
-
- /*!
- @brief returns x * y
- @note The result is rounded. (Only the upper q bits are returned.)
- */
- static diyfp mul(const diyfp& x, const diyfp& y) noexcept
- {
- static_assert(kPrecision == 64, "internal error");
-
- // Computes:
- // f = round((x.f * y.f) / 2^q)
- // e = x.e + y.e + q
-
- // Emulate the 64-bit * 64-bit multiplication:
- //
- // p = u * v
- // = (u_lo + 2^32 u_hi) (v_lo + 2^32 v_hi)
- // = (u_lo v_lo ) + 2^32 ((u_lo v_hi ) + (u_hi v_lo )) + 2^64 (u_hi v_hi )
- // = (p0 ) + 2^32 ((p1 ) + (p2 )) + 2^64 (p3 )
- // = (p0_lo + 2^32 p0_hi) + 2^32 ((p1_lo + 2^32 p1_hi) + (p2_lo + 2^32 p2_hi)) + 2^64 (p3 )
- // = (p0_lo ) + 2^32 (p0_hi + p1_lo + p2_lo ) + 2^64 (p1_hi + p2_hi + p3)
- // = (p0_lo ) + 2^32 (Q ) + 2^64 (H )
- // = (p0_lo ) + 2^32 (Q_lo + 2^32 Q_hi ) + 2^64 (H )
- //
- // (Since Q might be larger than 2^32 - 1)
- //
- // = (p0_lo + 2^32 Q_lo) + 2^64 (Q_hi + H)
- //
- // (Q_hi + H does not overflow a 64-bit int)
- //
- // = p_lo + 2^64 p_hi
-
- const uint64_t u_lo = x.f & 0xFFFFFFFF;
- const uint64_t u_hi = x.f >> 32;
- const uint64_t v_lo = y.f & 0xFFFFFFFF;
- const uint64_t v_hi = y.f >> 32;
-
- const uint64_t p0 = u_lo * v_lo;
- const uint64_t p1 = u_lo * v_hi;
- const uint64_t p2 = u_hi * v_lo;
- const uint64_t p3 = u_hi * v_hi;
-
- const uint64_t p0_hi = p0 >> 32;
- const uint64_t p1_lo = p1 & 0xFFFFFFFF;
- const uint64_t p1_hi = p1 >> 32;
- const uint64_t p2_lo = p2 & 0xFFFFFFFF;
- const uint64_t p2_hi = p2 >> 32;
-
- uint64_t Q = p0_hi + p1_lo + p2_lo;
-
- // The full product might now be computed as
- //
- // p_hi = p3 + p2_hi + p1_hi + (Q >> 32)
- // p_lo = p0_lo + (Q << 32)
- //
- // But in this particular case here, the full p_lo is not required.
- // Effectively we only need to add the highest bit in p_lo to p_hi (and
- // Q_hi + 1 does not overflow).
-
- Q += uint64_t{1} << (64 - 32 - 1); // round, ties up
-
- const uint64_t h = p3 + p2_hi + p1_hi + (Q >> 32);
-
- return {h, x.e + y.e + 64};
- }
-
- /*!
- @brief normalize x such that the significand is >= 2^(q-1)
- @pre x.f != 0
- */
- static diyfp normalize(diyfp x) noexcept
- {
- assert(x.f != 0);
-
- while ((x.f >> 63) == 0)
- {
- x.f <<= 1;
- x.e--;
- }
-
- return x;
- }
-
- /*!
- @brief normalize x such that the result has the exponent E
- @pre e >= x.e and the upper e - x.e bits of x.f must be zero.
- */
- static diyfp normalize_to(const diyfp& x, const int target_exponent) noexcept
- {
- const int delta = x.e - target_exponent;
-
- assert(delta >= 0);
- assert(((x.f << delta) >> delta) == x.f);
-
- return {x.f << delta, target_exponent};
- }
-};
-
-struct boundaries
-{
- diyfp w;
- diyfp minus;
- diyfp plus;
-};
-
-/*!
-Compute the (normalized) diyfp representing the input number 'value' and its
-boundaries.
-
-@pre value must be finite and positive
-*/
-template <typename FloatType>
-boundaries compute_boundaries(FloatType value)
-{
- assert(std::isfinite(value));
- assert(value > 0);
-
- // Convert the IEEE representation into a diyfp.
- //
- // If v is denormal:
- // value = 0.F * 2^(1 - bias) = ( F) * 2^(1 - bias - (p-1))
- // If v is normalized:
- // value = 1.F * 2^(E - bias) = (2^(p-1) + F) * 2^(E - bias - (p-1))
-
- static_assert(std::numeric_limits<FloatType>::is_iec559,
- "internal error: dtoa_short requires an IEEE-754 floating-point implementation");
-
- constexpr int kPrecision = std::numeric_limits<FloatType>::digits; // = p (includes the hidden bit)
- constexpr int kBias = std::numeric_limits<FloatType>::max_exponent - 1 + (kPrecision - 1);
- constexpr int kMinExp = 1 - kBias;
- constexpr uint64_t kHiddenBit = uint64_t{1} << (kPrecision - 1); // = 2^(p-1)
-
- using bits_type = typename std::conditional< kPrecision == 24, uint32_t, uint64_t >::type;
-
- const uint64_t bits = reinterpret_bits<bits_type>(value);
- const uint64_t E = bits >> (kPrecision - 1);
- const uint64_t F = bits & (kHiddenBit - 1);
-
- const bool is_denormal = (E == 0);
- const diyfp v = is_denormal
- ? diyfp(F, kMinExp)
- : diyfp(F + kHiddenBit, static_cast<int>(E) - kBias);
-
- // Compute the boundaries m- and m+ of the floating-point value
- // v = f * 2^e.
- //
- // Determine v- and v+, the floating-point predecessor and successor if v,
- // respectively.
- //
- // v- = v - 2^e if f != 2^(p-1) or e == e_min (A)
- // = v - 2^(e-1) if f == 2^(p-1) and e > e_min (B)
- //
- // v+ = v + 2^e
- //
- // Let m- = (v- + v) / 2 and m+ = (v + v+) / 2. All real numbers _strictly_
- // between m- and m+ round to v, regardless of how the input rounding
- // algorithm breaks ties.
- //
- // ---+-------------+-------------+-------------+-------------+--- (A)
- // v- m- v m+ v+
- //
- // -----------------+------+------+-------------+-------------+--- (B)
- // v- m- v m+ v+
-
- const bool lower_boundary_is_closer = (F == 0 and E > 1);
- const diyfp m_plus = diyfp(2 * v.f + 1, v.e - 1);
- const diyfp m_minus = lower_boundary_is_closer
- ? diyfp(4 * v.f - 1, v.e - 2) // (B)
- : diyfp(2 * v.f - 1, v.e - 1); // (A)
-
- // Determine the normalized w+ = m+.
- const diyfp w_plus = diyfp::normalize(m_plus);
-
- // Determine w- = m- such that e_(w-) = e_(w+).
- const diyfp w_minus = diyfp::normalize_to(m_minus, w_plus.e);
-
- return {diyfp::normalize(v), w_minus, w_plus};
-}
-
-// Given normalized diyfp w, Grisu needs to find a (normalized) cached
-// power-of-ten c, such that the exponent of the product c * w = f * 2^e lies
-// within a certain range [alpha, gamma] (Definition 3.2 from [1])
-//
-// alpha <= e = e_c + e_w + q <= gamma
-//
-// or
-//
-// f_c * f_w * 2^alpha <= f_c 2^(e_c) * f_w 2^(e_w) * 2^q
-// <= f_c * f_w * 2^gamma
-//
-// Since c and w are normalized, i.e. 2^(q-1) <= f < 2^q, this implies
-//
-// 2^(q-1) * 2^(q-1) * 2^alpha <= c * w * 2^q < 2^q * 2^q * 2^gamma
-//
-// or
-//
-// 2^(q - 2 + alpha) <= c * w < 2^(q + gamma)
-//
-// The choice of (alpha,gamma) determines the size of the table and the form of
-// the digit generation procedure. Using (alpha,gamma)=(-60,-32) works out well
-// in practice:
-//
-// The idea is to cut the number c * w = f * 2^e into two parts, which can be
-// processed independently: An integral part p1, and a fractional part p2:
-//
-// f * 2^e = ( (f div 2^-e) * 2^-e + (f mod 2^-e) ) * 2^e
-// = (f div 2^-e) + (f mod 2^-e) * 2^e
-// = p1 + p2 * 2^e
-//
-// The conversion of p1 into decimal form requires a series of divisions and
-// modulos by (a power of) 10. These operations are faster for 32-bit than for
-// 64-bit integers, so p1 should ideally fit into a 32-bit integer. This can be
-// achieved by choosing
-//
-// -e >= 32 or e <= -32 := gamma
-//
-// In order to convert the fractional part
-//
-// p2 * 2^e = p2 / 2^-e = d[-1] / 10^1 + d[-2] / 10^2 + ...
-//
-// into decimal form, the fraction is repeatedly multiplied by 10 and the digits
-// d[-i] are extracted in order:
-//
-// (10 * p2) div 2^-e = d[-1]
-// (10 * p2) mod 2^-e = d[-2] / 10^1 + ...
-//
-// The multiplication by 10 must not overflow. It is sufficient to choose
-//
-// 10 * p2 < 16 * p2 = 2^4 * p2 <= 2^64.
-//
-// Since p2 = f mod 2^-e < 2^-e,
-//
-// -e <= 60 or e >= -60 := alpha
-
-constexpr int kAlpha = -60;
-constexpr int kGamma = -32;
-
-struct cached_power // c = f * 2^e ~= 10^k
-{
- uint64_t f;
- int e;
- int k;
-};
-
-/*!
-For a normalized diyfp w = f * 2^e, this function returns a (normalized) cached
-power-of-ten c = f_c * 2^e_c, such that the exponent of the product w * c
-satisfies (Definition 3.2 from [1])
-
- alpha <= e_c + e + q <= gamma.
-*/
-inline cached_power get_cached_power_for_binary_exponent(int e)
-{
- // Now
- //
- // alpha <= e_c + e + q <= gamma (1)
- // ==> f_c * 2^alpha <= c * 2^e * 2^q
- //
- // and since the c's are normalized, 2^(q-1) <= f_c,
- //
- // ==> 2^(q - 1 + alpha) <= c * 2^(e + q)
- // ==> 2^(alpha - e - 1) <= c
- //
- // If c were an exakt power of ten, i.e. c = 10^k, one may determine k as
- //
- // k = ceil( log_10( 2^(alpha - e - 1) ) )
- // = ceil( (alpha - e - 1) * log_10(2) )
- //
- // From the paper:
- // "In theory the result of the procedure could be wrong since c is rounded,
- // and the computation itself is approximated [...]. In practice, however,
- // this simple function is sufficient."
- //
- // For IEEE double precision floating-point numbers converted into
- // normalized diyfp's w = f * 2^e, with q = 64,
- //
- // e >= -1022 (min IEEE exponent)
- // -52 (p - 1)
- // -52 (p - 1, possibly normalize denormal IEEE numbers)
- // -11 (normalize the diyfp)
- // = -1137
- //
- // and
- //
- // e <= +1023 (max IEEE exponent)
- // -52 (p - 1)
- // -11 (normalize the diyfp)
- // = 960
- //
- // This binary exponent range [-1137,960] results in a decimal exponent
- // range [-307,324]. One does not need to store a cached power for each
- // k in this range. For each such k it suffices to find a cached power
- // such that the exponent of the product lies in [alpha,gamma].
- // This implies that the difference of the decimal exponents of adjacent
- // table entries must be less than or equal to
- //
- // floor( (gamma - alpha) * log_10(2) ) = 8.
- //
- // (A smaller distance gamma-alpha would require a larger table.)
-
- // NB:
- // Actually this function returns c, such that -60 <= e_c + e + 64 <= -34.
-
- constexpr int kCachedPowersSize = 79;
- constexpr int kCachedPowersMinDecExp = -300;
- constexpr int kCachedPowersDecStep = 8;
-
- static constexpr cached_power kCachedPowers[] =
- {
- { 0xAB70FE17C79AC6CA, -1060, -300 },
- { 0xFF77B1FCBEBCDC4F, -1034, -292 },
- { 0xBE5691EF416BD60C, -1007, -284 },
- { 0x8DD01FAD907FFC3C, -980, -276 },
- { 0xD3515C2831559A83, -954, -268 },
- { 0x9D71AC8FADA6C9B5, -927, -260 },
- { 0xEA9C227723EE8BCB, -901, -252 },
- { 0xAECC49914078536D, -874, -244 },
- { 0x823C12795DB6CE57, -847, -236 },
- { 0xC21094364DFB5637, -821, -228 },
- { 0x9096EA6F3848984F, -794, -220 },
- { 0xD77485CB25823AC7, -768, -212 },
- { 0xA086CFCD97BF97F4, -741, -204 },
- { 0xEF340A98172AACE5, -715, -196 },
- { 0xB23867FB2A35B28E, -688, -188 },
- { 0x84C8D4DFD2C63F3B, -661, -180 },
- { 0xC5DD44271AD3CDBA, -635, -172 },
- { 0x936B9FCEBB25C996, -608, -164 },
- { 0xDBAC6C247D62A584, -582, -156 },
- { 0xA3AB66580D5FDAF6, -555, -148 },
- { 0xF3E2F893DEC3F126, -529, -140 },
- { 0xB5B5ADA8AAFF80B8, -502, -132 },
- { 0x87625F056C7C4A8B, -475, -124 },
- { 0xC9BCFF6034C13053, -449, -116 },
- { 0x964E858C91BA2655, -422, -108 },
- { 0xDFF9772470297EBD, -396, -100 },
- { 0xA6DFBD9FB8E5B88F, -369, -92 },
- { 0xF8A95FCF88747D94, -343, -84 },
- { 0xB94470938FA89BCF, -316, -76 },
- { 0x8A08F0F8BF0F156B, -289, -68 },
- { 0xCDB02555653131B6, -263, -60 },
- { 0x993FE2C6D07B7FAC, -236, -52 },
- { 0xE45C10C42A2B3B06, -210, -44 },
- { 0xAA242499697392D3, -183, -36 },
- { 0xFD87B5F28300CA0E, -157, -28 },
- { 0xBCE5086492111AEB, -130, -20 },
- { 0x8CBCCC096F5088CC, -103, -12 },
- { 0xD1B71758E219652C, -77, -4 },
- { 0x9C40000000000000, -50, 4 },
- { 0xE8D4A51000000000, -24, 12 },
- { 0xAD78EBC5AC620000, 3, 20 },
- { 0x813F3978F8940984, 30, 28 },
- { 0xC097CE7BC90715B3, 56, 36 },
- { 0x8F7E32CE7BEA5C70, 83, 44 },
- { 0xD5D238A4ABE98068, 109, 52 },
- { 0x9F4F2726179A2245, 136, 60 },
- { 0xED63A231D4C4FB27, 162, 68 },
- { 0xB0DE65388CC8ADA8, 189, 76 },
- { 0x83C7088E1AAB65DB, 216, 84 },
- { 0xC45D1DF942711D9A, 242, 92 },
- { 0x924D692CA61BE758, 269, 100 },
- { 0xDA01EE641A708DEA, 295, 108 },
- { 0xA26DA3999AEF774A, 322, 116 },
- { 0xF209787BB47D6B85, 348, 124 },
- { 0xB454E4A179DD1877, 375, 132 },
- { 0x865B86925B9BC5C2, 402, 140 },
- { 0xC83553C5C8965D3D, 428, 148 },
- { 0x952AB45CFA97A0B3, 455, 156 },
- { 0xDE469FBD99A05FE3, 481, 164 },
- { 0xA59BC234DB398C25, 508, 172 },
- { 0xF6C69A72A3989F5C, 534, 180 },
- { 0xB7DCBF5354E9BECE, 561, 188 },
- { 0x88FCF317F22241E2, 588, 196 },
- { 0xCC20CE9BD35C78A5, 614, 204 },
- { 0x98165AF37B2153DF, 641, 212 },
- { 0xE2A0B5DC971F303A, 667, 220 },
- { 0xA8D9D1535CE3B396, 694, 228 },
- { 0xFB9B7CD9A4A7443C, 720, 236 },
- { 0xBB764C4CA7A44410, 747, 244 },
- { 0x8BAB8EEFB6409C1A, 774, 252 },
- { 0xD01FEF10A657842C, 800, 260 },
- { 0x9B10A4E5E9913129, 827, 268 },
- { 0xE7109BFBA19C0C9D, 853, 276 },
- { 0xAC2820D9623BF429, 880, 284 },
- { 0x80444B5E7AA7CF85, 907, 292 },
- { 0xBF21E44003ACDD2D, 933, 300 },
- { 0x8E679C2F5E44FF8F, 960, 308 },
- { 0xD433179D9C8CB841, 986, 316 },
- { 0x9E19DB92B4E31BA9, 1013, 324 },
- };
-
- // This computation gives exactly the same results for k as
- // k = ceil((kAlpha - e - 1) * 0.30102999566398114)
- // for |e| <= 1500, but doesn't require floating-point operations.
- // NB: log_10(2) ~= 78913 / 2^18
- assert(e >= -1500);
- assert(e <= 1500);
- const int f = kAlpha - e - 1;
- const int k = (f * 78913) / (1 << 18) + static_cast<int>(f > 0);
-
- const int index = (-kCachedPowersMinDecExp + k + (kCachedPowersDecStep - 1)) / kCachedPowersDecStep;
- assert(index >= 0);
- assert(index < kCachedPowersSize);
- static_cast<void>(kCachedPowersSize); // Fix warning.
-
- const cached_power cached = kCachedPowers[index];
- assert(kAlpha <= cached.e + e + 64);
- assert(kGamma >= cached.e + e + 64);
-
- return cached;
-}
-
-/*!
-For n != 0, returns k, such that pow10 := 10^(k-1) <= n < 10^k.
-For n == 0, returns 1 and sets pow10 := 1.
-*/
-inline int find_largest_pow10(const uint32_t n, uint32_t& pow10)
-{
- // LCOV_EXCL_START
- if (n >= 1000000000)
- {
- pow10 = 1000000000;
- return 10;
- }
- // LCOV_EXCL_STOP
- else if (n >= 100000000)
- {
- pow10 = 100000000;
- return 9;
- }
- else if (n >= 10000000)
- {
- pow10 = 10000000;
- return 8;
- }
- else if (n >= 1000000)
- {
- pow10 = 1000000;
- return 7;
- }
- else if (n >= 100000)
- {
- pow10 = 100000;
- return 6;
- }
- else if (n >= 10000)
- {
- pow10 = 10000;
- return 5;
- }
- else if (n >= 1000)
- {
- pow10 = 1000;
- return 4;
- }
- else if (n >= 100)
- {
- pow10 = 100;
- return 3;
- }
- else if (n >= 10)
- {
- pow10 = 10;
- return 2;
- }
- else
- {
- pow10 = 1;
- return 1;
- }
-}
-
-inline void grisu2_round(char* buf, int len, uint64_t dist, uint64_t delta,
- uint64_t rest, uint64_t ten_k)
-{
- assert(len >= 1);
- assert(dist <= delta);
- assert(rest <= delta);
- assert(ten_k > 0);
-
- // <--------------------------- delta ---->
- // <---- dist --------->
- // --------------[------------------+-------------------]--------------
- // M- w M+
- //
- // ten_k
- // <------>
- // <---- rest ---->
- // --------------[------------------+----+--------------]--------------
- // w V
- // = buf * 10^k
- //
- // ten_k represents a unit-in-the-last-place in the decimal representation
- // stored in buf.
- // Decrement buf by ten_k while this takes buf closer to w.
-
- // The tests are written in this order to avoid overflow in unsigned
- // integer arithmetic.
-
- while (rest < dist
- and delta - rest >= ten_k
- and (rest + ten_k < dist or dist - rest > rest + ten_k - dist))
- {
- assert(buf[len - 1] != '0');
- buf[len - 1]--;
- rest += ten_k;
- }
-}
-
-/*!
-Generates V = buffer * 10^decimal_exponent, such that M- <= V <= M+.
-M- and M+ must be normalized and share the same exponent -60 <= e <= -32.
-*/
-inline void grisu2_digit_gen(char* buffer, int& length, int& decimal_exponent,
- diyfp M_minus, diyfp w, diyfp M_plus)
-{
- static_assert(kAlpha >= -60, "internal error");
- static_assert(kGamma <= -32, "internal error");
-
- // Generates the digits (and the exponent) of a decimal floating-point
- // number V = buffer * 10^decimal_exponent in the range [M-, M+]. The diyfp's
- // w, M- and M+ share the same exponent e, which satisfies alpha <= e <= gamma.
- //
- // <--------------------------- delta ---->
- // <---- dist --------->
- // --------------[------------------+-------------------]--------------
- // M- w M+
- //
- // Grisu2 generates the digits of M+ from left to right and stops as soon as
- // V is in [M-,M+].
-
- assert(M_plus.e >= kAlpha);
- assert(M_plus.e <= kGamma);
-
- uint64_t delta = diyfp::sub(M_plus, M_minus).f; // (significand of (M+ - M-), implicit exponent is e)
- uint64_t dist = diyfp::sub(M_plus, w ).f; // (significand of (M+ - w ), implicit exponent is e)
-
- // Split M+ = f * 2^e into two parts p1 and p2 (note: e < 0):
- //
- // M+ = f * 2^e
- // = ((f div 2^-e) * 2^-e + (f mod 2^-e)) * 2^e
- // = ((p1 ) * 2^-e + (p2 )) * 2^e
- // = p1 + p2 * 2^e
-
- const diyfp one(uint64_t{1} << -M_plus.e, M_plus.e);
-
- auto p1 = static_cast<uint32_t>(M_plus.f >> -one.e); // p1 = f div 2^-e (Since -e >= 32, p1 fits into a 32-bit int.)
- uint64_t p2 = M_plus.f & (one.f - 1); // p2 = f mod 2^-e
-
- // 1)
- //
- // Generate the digits of the integral part p1 = d[n-1]...d[1]d[0]
-
- assert(p1 > 0);
-
- uint32_t pow10;
- const int k = find_largest_pow10(p1, pow10);
-
- // 10^(k-1) <= p1 < 10^k, pow10 = 10^(k-1)
- //
- // p1 = (p1 div 10^(k-1)) * 10^(k-1) + (p1 mod 10^(k-1))
- // = (d[k-1] ) * 10^(k-1) + (p1 mod 10^(k-1))
- //
- // M+ = p1 + p2 * 2^e
- // = d[k-1] * 10^(k-1) + (p1 mod 10^(k-1)) + p2 * 2^e
- // = d[k-1] * 10^(k-1) + ((p1 mod 10^(k-1)) * 2^-e + p2) * 2^e
- // = d[k-1] * 10^(k-1) + ( rest) * 2^e
- //
- // Now generate the digits d[n] of p1 from left to right (n = k-1,...,0)
- //
- // p1 = d[k-1]...d[n] * 10^n + d[n-1]...d[0]
- //
- // but stop as soon as
- //
- // rest * 2^e = (d[n-1]...d[0] * 2^-e + p2) * 2^e <= delta * 2^e
-
- int n = k;
- while (n > 0)
- {
- // Invariants:
- // M+ = buffer * 10^n + (p1 + p2 * 2^e) (buffer = 0 for n = k)
- // pow10 = 10^(n-1) <= p1 < 10^n
- //
- const uint32_t d = p1 / pow10; // d = p1 div 10^(n-1)
- const uint32_t r = p1 % pow10; // r = p1 mod 10^(n-1)
- //
- // M+ = buffer * 10^n + (d * 10^(n-1) + r) + p2 * 2^e
- // = (buffer * 10 + d) * 10^(n-1) + (r + p2 * 2^e)
- //
- assert(d <= 9);
- buffer[length++] = static_cast<char>('0' + d); // buffer := buffer * 10 + d
- //
- // M+ = buffer * 10^(n-1) + (r + p2 * 2^e)
- //
- p1 = r;
- n--;
- //
- // M+ = buffer * 10^n + (p1 + p2 * 2^e)
- // pow10 = 10^n
- //
-
- // Now check if enough digits have been generated.
- // Compute
- //
- // p1 + p2 * 2^e = (p1 * 2^-e + p2) * 2^e = rest * 2^e
- //
- // Note:
- // Since rest and delta share the same exponent e, it suffices to
- // compare the significands.
- const uint64_t rest = (uint64_t{p1} << -one.e) + p2;
- if (rest <= delta)
- {
- // V = buffer * 10^n, with M- <= V <= M+.
-
- decimal_exponent += n;
-
- // We may now just stop. But instead look if the buffer could be
- // decremented to bring V closer to w.
- //
- // pow10 = 10^n is now 1 ulp in the decimal representation V.
- // The rounding procedure works with diyfp's with an implicit
- // exponent of e.
- //
- // 10^n = (10^n * 2^-e) * 2^e = ulp * 2^e
- //
- const uint64_t ten_n = uint64_t{pow10} << -one.e;
- grisu2_round(buffer, length, dist, delta, rest, ten_n);
-
- return;
- }
-
- pow10 /= 10;
- //
- // pow10 = 10^(n-1) <= p1 < 10^n
- // Invariants restored.
- }
-
- // 2)
- //
- // The digits of the integral part have been generated:
- //
- // M+ = d[k-1]...d[1]d[0] + p2 * 2^e
- // = buffer + p2 * 2^e
- //
- // Now generate the digits of the fractional part p2 * 2^e.
- //
- // Note:
- // No decimal point is generated: the exponent is adjusted instead.
- //
- // p2 actually represents the fraction
- //
- // p2 * 2^e
- // = p2 / 2^-e
- // = d[-1] / 10^1 + d[-2] / 10^2 + ...
- //
- // Now generate the digits d[-m] of p1 from left to right (m = 1,2,...)
- //
- // p2 * 2^e = d[-1]d[-2]...d[-m] * 10^-m
- // + 10^-m * (d[-m-1] / 10^1 + d[-m-2] / 10^2 + ...)
- //
- // using
- //
- // 10^m * p2 = ((10^m * p2) div 2^-e) * 2^-e + ((10^m * p2) mod 2^-e)
- // = ( d) * 2^-e + ( r)
- //
- // or
- // 10^m * p2 * 2^e = d + r * 2^e
- //
- // i.e.
- //
- // M+ = buffer + p2 * 2^e
- // = buffer + 10^-m * (d + r * 2^e)
- // = (buffer * 10^m + d) * 10^-m + 10^-m * r * 2^e
- //
- // and stop as soon as 10^-m * r * 2^e <= delta * 2^e
-
- assert(p2 > delta);
-
- int m = 0;
- for (;;)
- {
- // Invariant:
- // M+ = buffer * 10^-m + 10^-m * (d[-m-1] / 10 + d[-m-2] / 10^2 + ...) * 2^e
- // = buffer * 10^-m + 10^-m * (p2 ) * 2^e
- // = buffer * 10^-m + 10^-m * (1/10 * (10 * p2) ) * 2^e
- // = buffer * 10^-m + 10^-m * (1/10 * ((10*p2 div 2^-e) * 2^-e + (10*p2 mod 2^-e)) * 2^e
- //
- assert(p2 <= UINT64_MAX / 10);
- p2 *= 10;
- const uint64_t d = p2 >> -one.e; // d = (10 * p2) div 2^-e
- const uint64_t r = p2 & (one.f - 1); // r = (10 * p2) mod 2^-e
- //
- // M+ = buffer * 10^-m + 10^-m * (1/10 * (d * 2^-e + r) * 2^e
- // = buffer * 10^-m + 10^-m * (1/10 * (d + r * 2^e))
- // = (buffer * 10 + d) * 10^(-m-1) + 10^(-m-1) * r * 2^e
- //
- assert(d <= 9);
- buffer[length++] = static_cast<char>('0' + d); // buffer := buffer * 10 + d
- //
- // M+ = buffer * 10^(-m-1) + 10^(-m-1) * r * 2^e
- //
- p2 = r;
- m++;
- //
- // M+ = buffer * 10^-m + 10^-m * p2 * 2^e
- // Invariant restored.
-
- // Check if enough digits have been generated.
- //
- // 10^-m * p2 * 2^e <= delta * 2^e
- // p2 * 2^e <= 10^m * delta * 2^e
- // p2 <= 10^m * delta
- delta *= 10;
- dist *= 10;
- if (p2 <= delta)
- {
- break;
- }
- }
-
- // V = buffer * 10^-m, with M- <= V <= M+.
-
- decimal_exponent -= m;
-
- // 1 ulp in the decimal representation is now 10^-m.
- // Since delta and dist are now scaled by 10^m, we need to do the
- // same with ulp in order to keep the units in sync.
- //
- // 10^m * 10^-m = 1 = 2^-e * 2^e = ten_m * 2^e
- //
- const uint64_t ten_m = one.f;
- grisu2_round(buffer, length, dist, delta, p2, ten_m);
-
- // By construction this algorithm generates the shortest possible decimal
- // number (Loitsch, Theorem 6.2) which rounds back to w.
- // For an input number of precision p, at least
- //
- // N = 1 + ceil(p * log_10(2))
- //
- // decimal digits are sufficient to identify all binary floating-point
- // numbers (Matula, "In-and-Out conversions").
- // This implies that the algorithm does not produce more than N decimal
- // digits.
- //
- // N = 17 for p = 53 (IEEE double precision)
- // N = 9 for p = 24 (IEEE single precision)
-}
-
-/*!
-v = buf * 10^decimal_exponent
-len is the length of the buffer (number of decimal digits)
-The buffer must be large enough, i.e. >= max_digits10.
-*/
-inline void grisu2(char* buf, int& len, int& decimal_exponent,
- diyfp m_minus, diyfp v, diyfp m_plus)
-{
- assert(m_plus.e == m_minus.e);
- assert(m_plus.e == v.e);
-
- // --------(-----------------------+-----------------------)-------- (A)
- // m- v m+
- //
- // --------------------(-----------+-----------------------)-------- (B)
- // m- v m+
- //
- // First scale v (and m- and m+) such that the exponent is in the range
- // [alpha, gamma].
-
- const cached_power cached = get_cached_power_for_binary_exponent(m_plus.e);
-
- const diyfp c_minus_k(cached.f, cached.e); // = c ~= 10^-k
-
- // The exponent of the products is = v.e + c_minus_k.e + q and is in the range [alpha,gamma]
- const diyfp w = diyfp::mul(v, c_minus_k);
- const diyfp w_minus = diyfp::mul(m_minus, c_minus_k);
- const diyfp w_plus = diyfp::mul(m_plus, c_minus_k);
-
- // ----(---+---)---------------(---+---)---------------(---+---)----
- // w- w w+
- // = c*m- = c*v = c*m+
- //
- // diyfp::mul rounds its result and c_minus_k is approximated too. w, w- and
- // w+ are now off by a small amount.
- // In fact:
- //
- // w - v * 10^k < 1 ulp
- //
- // To account for this inaccuracy, add resp. subtract 1 ulp.
- //
- // --------+---[---------------(---+---)---------------]---+--------
- // w- M- w M+ w+
- //
- // Now any number in [M-, M+] (bounds included) will round to w when input,
- // regardless of how the input rounding algorithm breaks ties.
- //
- // And digit_gen generates the shortest possible such number in [M-, M+].
- // Note that this does not mean that Grisu2 always generates the shortest
- // possible number in the interval (m-, m+).
- const diyfp M_minus(w_minus.f + 1, w_minus.e);
- const diyfp M_plus (w_plus.f - 1, w_plus.e );
-
- decimal_exponent = -cached.k; // = -(-k) = k
-
- grisu2_digit_gen(buf, len, decimal_exponent, M_minus, w, M_plus);
-}
-
-/*!
-v = buf * 10^decimal_exponent
-len is the length of the buffer (number of decimal digits)
-The buffer must be large enough, i.e. >= max_digits10.
-*/
-template <typename FloatType>
-void grisu2(char* buf, int& len, int& decimal_exponent, FloatType value)
-{
- static_assert(diyfp::kPrecision >= std::numeric_limits<FloatType>::digits + 3,
- "internal error: not enough precision");
-
- assert(std::isfinite(value));
- assert(value > 0);
-
- // If the neighbors (and boundaries) of 'value' are always computed for double-precision
- // numbers, all float's can be recovered using strtod (and strtof). However, the resulting
- // decimal representations are not exactly "short".
- //
- // The documentation for 'std::to_chars' (https://en.cppreference.com/w/cpp/utility/to_chars)
- // says "value is converted to a string as if by std::sprintf in the default ("C") locale"
- // and since sprintf promotes float's to double's, I think this is exactly what 'std::to_chars'
- // does.
- // On the other hand, the documentation for 'std::to_chars' requires that "parsing the
- // representation using the corresponding std::from_chars function recovers value exactly". That
- // indicates that single precision floating-point numbers should be recovered using
- // 'std::strtof'.
- //
- // NB: If the neighbors are computed for single-precision numbers, there is a single float
- // (7.0385307e-26f) which can't be recovered using strtod. The resulting double precision
- // value is off by 1 ulp.
-#if 0
- const boundaries w = compute_boundaries(static_cast<double>(value));
-#else
- const boundaries w = compute_boundaries(value);
-#endif
-
- grisu2(buf, len, decimal_exponent, w.minus, w.w, w.plus);
-}
-
-/*!
-@brief appends a decimal representation of e to buf
-@return a pointer to the element following the exponent.
-@pre -1000 < e < 1000
-*/
-inline char* append_exponent(char* buf, int e)
-{
- assert(e > -1000);
- assert(e < 1000);
-
- if (e < 0)
- {
- e = -e;
- *buf++ = '-';
- }
- else
- {
- *buf++ = '+';
- }
-
- auto k = static_cast<uint32_t>(e);
- if (k < 10)
- {
- // Always print at least two digits in the exponent.
- // This is for compatibility with printf("%g").
- *buf++ = '0';
- *buf++ = static_cast<char>('0' + k);
- }
- else if (k < 100)
- {
- *buf++ = static_cast<char>('0' + k / 10);
- k %= 10;
- *buf++ = static_cast<char>('0' + k);
- }
- else
- {
- *buf++ = static_cast<char>('0' + k / 100);
- k %= 100;
- *buf++ = static_cast<char>('0' + k / 10);
- k %= 10;
- *buf++ = static_cast<char>('0' + k);
- }
-
- return buf;
-}
-
-/*!
-@brief prettify v = buf * 10^decimal_exponent
-
-If v is in the range [10^min_exp, 10^max_exp) it will be printed in fixed-point
-notation. Otherwise it will be printed in exponential notation.
-
-@pre min_exp < 0
-@pre max_exp > 0
-*/
-inline char* format_buffer(char* buf, int len, int decimal_exponent,
- int min_exp, int max_exp)
-{
- assert(min_exp < 0);
- assert(max_exp > 0);
-
- const int k = len;
- const int n = len + decimal_exponent;
-
- // v = buf * 10^(n-k)
- // k is the length of the buffer (number of decimal digits)
- // n is the position of the decimal point relative to the start of the buffer.
-
- if (k <= n and n <= max_exp)
- {
- // digits[000]
- // len <= max_exp + 2
-
- std::memset(buf + k, '0', static_cast<size_t>(n - k));
- // Make it look like a floating-point number (#362, #378)
- buf[n + 0] = '.';
- buf[n + 1] = '0';
- return buf + (n + 2);
- }
-
- if (0 < n and n <= max_exp)
- {
- // dig.its
- // len <= max_digits10 + 1
-
- assert(k > n);
-
- std::memmove(buf + (n + 1), buf + n, static_cast<size_t>(k - n));
- buf[n] = '.';
- return buf + (k + 1);
- }
-
- if (min_exp < n and n <= 0)
- {
- // 0.[000]digits
- // len <= 2 + (-min_exp - 1) + max_digits10
-
- std::memmove(buf + (2 + -n), buf, static_cast<size_t>(k));
- buf[0] = '0';
- buf[1] = '.';
- std::memset(buf + 2, '0', static_cast<size_t>(-n));
- return buf + (2 + (-n) + k);
- }
-
- if (k == 1)
- {
- // dE+123
- // len <= 1 + 5
-
- buf += 1;
- }
- else
- {
- // d.igitsE+123
- // len <= max_digits10 + 1 + 5
-
- std::memmove(buf + 2, buf + 1, static_cast<size_t>(k - 1));
- buf[1] = '.';
- buf += 1 + k;
- }
-
- *buf++ = 'e';
- return append_exponent(buf, n - 1);
-}
-
-} // namespace dtoa_impl
-
-/*!
-@brief generates a decimal representation of the floating-point number value in [first, last).
-
-The format of the resulting decimal representation is similar to printf's %g
-format. Returns an iterator pointing past-the-end of the decimal representation.
-
-@note The input number must be finite, i.e. NaN's and Inf's are not supported.
-@note The buffer must be large enough.
-@note The result is NOT null-terminated.
-*/
-template <typename FloatType>
-char* to_chars(char* first, const char* last, FloatType value)
-{
- static_cast<void>(last); // maybe unused - fix warning
- assert(std::isfinite(value));
-
- // Use signbit(value) instead of (value < 0) since signbit works for -0.
- if (std::signbit(value))
- {
- value = -value;
- *first++ = '-';
- }
-
- if (value == 0) // +-0
- {
- *first++ = '0';
- // Make it look like a floating-point number (#362, #378)
- *first++ = '.';
- *first++ = '0';
- return first;
- }
-
- assert(last - first >= std::numeric_limits<FloatType>::max_digits10);
-
- // Compute v = buffer * 10^decimal_exponent.
- // The decimal digits are stored in the buffer, which needs to be interpreted
- // as an unsigned decimal integer.
- // len is the length of the buffer, i.e. the number of decimal digits.
- int len = 0;
- int decimal_exponent = 0;
- dtoa_impl::grisu2(first, len, decimal_exponent, value);
-
- assert(len <= std::numeric_limits<FloatType>::max_digits10);
-
- // Format the buffer like printf("%.*g", prec, value)
- constexpr int kMinExp = -4;
- // Use digits10 here to increase compatibility with version 2.
- constexpr int kMaxExp = std::numeric_limits<FloatType>::digits10;
-
- assert(last - first >= kMaxExp + 2);
- assert(last - first >= 2 + (-kMinExp - 1) + std::numeric_limits<FloatType>::max_digits10);
- assert(last - first >= std::numeric_limits<FloatType>::max_digits10 + 6);
-
- return dtoa_impl::format_buffer(first, len, decimal_exponent, kMinExp, kMaxExp);
-}
-
-} // namespace detail
-} // namespace nlohmann
diff --git a/include/lib/modernjson/detail/conversions/to_json.hpp b/include/lib/modernjson/detail/conversions/to_json.hpp
deleted file mode 100644
index 5c3669c..0000000
--- a/include/lib/modernjson/detail/conversions/to_json.hpp
+++ /dev/null
@@ -1,342 +0,0 @@
-#pragma once
-
-#include <ciso646> // or, and, not
-#include <iterator> // begin, end
-#include <tuple> // tuple, get
-#include <type_traits> // is_same, is_constructible, is_floating_point, is_enum, underlying_type
-#include <utility> // move, forward, declval, pair
-#include <valarray> // valarray
-#include <vector> // vector
-
-#include <lib/modernjson/detail/meta/cpp_future.hpp>
-#include <lib/modernjson/detail/meta/type_traits.hpp>
-#include <lib/modernjson/detail/value_t.hpp>
-#include <lib/modernjson/detail/iterators/iteration_proxy.hpp>
-
-namespace nlohmann
-{
-namespace detail
-{
-//////////////////
-// constructors //
-//////////////////
-
-template<value_t> struct external_constructor;
-
-template<>
-struct external_constructor<value_t::boolean>
-{
- template<typename BasicJsonType>
- static void construct(BasicJsonType& j, typename BasicJsonType::boolean_t b) noexcept
- {
- j.m_type = value_t::boolean;
- j.m_value = b;
- j.assert_invariant();
- }
-};
-
-template<>
-struct external_constructor<value_t::string>
-{
- template<typename BasicJsonType>
- static void construct(BasicJsonType& j, const typename BasicJsonType::string_t& s)
- {
- j.m_type = value_t::string;
- j.m_value = s;
- j.assert_invariant();
- }
-
- template<typename BasicJsonType>
- static void construct(BasicJsonType& j, typename BasicJsonType::string_t&& s)
- {
- j.m_type = value_t::string;
- j.m_value = std::move(s);
- j.assert_invariant();
- }
-
- template<typename BasicJsonType, typename CompatibleStringType,
- enable_if_t<not std::is_same<CompatibleStringType, typename BasicJsonType::string_t>::value,
- int> = 0>
- static void construct(BasicJsonType& j, const CompatibleStringType& str)
- {
- j.m_type = value_t::string;
- j.m_value.string = j.template create<typename BasicJsonType::string_t>(str);
- j.assert_invariant();
- }
-};
-
-template<>
-struct external_constructor<value_t::number_float>
-{
- template<typename BasicJsonType>
- static void construct(BasicJsonType& j, typename BasicJsonType::number_float_t val) noexcept
- {
- j.m_type = value_t::number_float;
- j.m_value = val;
- j.assert_invariant();
- }
-};
-
-template<>
-struct external_constructor<value_t::number_unsigned>
-{
- template<typename BasicJsonType>
- static void construct(BasicJsonType& j, typename BasicJsonType::number_unsigned_t val) noexcept
- {
- j.m_type = value_t::number_unsigned;
- j.m_value = val;
- j.assert_invariant();
- }
-};
-
-template<>
-struct external_constructor<value_t::number_integer>
-{
- template<typename BasicJsonType>
- static void construct(BasicJsonType& j, typename BasicJsonType::number_integer_t val) noexcept
- {
- j.m_type = value_t::number_integer;
- j.m_value = val;
- j.assert_invariant();
- }
-};
-
-template<>
-struct external_constructor<value_t::array>
-{
- template<typename BasicJsonType>
- static void construct(BasicJsonType& j, const typename BasicJsonType::array_t& arr)
- {
- j.m_type = value_t::array;
- j.m_value = arr;
- j.assert_invariant();
- }
-
- template<typename BasicJsonType>
- static void construct(BasicJsonType& j, typename BasicJsonType::array_t&& arr)
- {
- j.m_type = value_t::array;
- j.m_value = std::move(arr);
- j.assert_invariant();
- }
-
- template<typename BasicJsonType, typename CompatibleArrayType,
- enable_if_t<not std::is_same<CompatibleArrayType, typename BasicJsonType::array_t>::value,
- int> = 0>
- static void construct(BasicJsonType& j, const CompatibleArrayType& arr)
- {
- using std::begin;
- using std::end;
- j.m_type = value_t::array;
- j.m_value.array = j.template create<typename BasicJsonType::array_t>(begin(arr), end(arr));
- j.assert_invariant();
- }
-
- template<typename BasicJsonType>
- static void construct(BasicJsonType& j, const std::vector<bool>& arr)
- {
- j.m_type = value_t::array;
- j.m_value = value_t::array;
- j.m_value.array->reserve(arr.size());
- for (const bool x : arr)
- {
- j.m_value.array->push_back(x);
- }
- j.assert_invariant();
- }
-
- template<typename BasicJsonType, typename T,
- enable_if_t<std::is_convertible<T, BasicJsonType>::value, int> = 0>
- static void construct(BasicJsonType& j, const std::valarray<T>& arr)
- {
- j.m_type = value_t::array;
- j.m_value = value_t::array;
- j.m_value.array->resize(arr.size());
- std::copy(std::begin(arr), std::end(arr), j.m_value.array->begin());
- j.assert_invariant();
- }
-};
-
-template<>
-struct external_constructor<value_t::object>
-{
- template<typename BasicJsonType>
- static void construct(BasicJsonType& j, const typename BasicJsonType::object_t& obj)
- {
- j.m_type = value_t::object;
- j.m_value = obj;
- j.assert_invariant();
- }
-
- template<typename BasicJsonType>
- static void construct(BasicJsonType& j, typename BasicJsonType::object_t&& obj)
- {
- j.m_type = value_t::object;
- j.m_value = std::move(obj);
- j.assert_invariant();
- }
-
- template<typename BasicJsonType, typename CompatibleObjectType,
- enable_if_t<not std::is_same<CompatibleObjectType, typename BasicJsonType::object_t>::value, int> = 0>
- static void construct(BasicJsonType& j, const CompatibleObjectType& obj)
- {
- using std::begin;
- using std::end;
-
- j.m_type = value_t::object;
- j.m_value.object = j.template create<typename BasicJsonType::object_t>(begin(obj), end(obj));
- j.assert_invariant();
- }
-};
-
-/////////////
-// to_json //
-/////////////
-
-template<typename BasicJsonType, typename T,
- enable_if_t<std::is_same<T, typename BasicJsonType::boolean_t>::value, int> = 0>
-void to_json(BasicJsonType& j, T b) noexcept
-{
- external_constructor<value_t::boolean>::construct(j, b);
-}
-
-template<typename BasicJsonType, typename CompatibleString,
- enable_if_t<std::is_constructible<typename BasicJsonType::string_t, CompatibleString>::value, int> = 0>
-void to_json(BasicJsonType& j, const CompatibleString& s)
-{
- external_constructor<value_t::string>::construct(j, s);
-}
-
-template<typename BasicJsonType>
-void to_json(BasicJsonType& j, typename BasicJsonType::string_t&& s)
-{
- external_constructor<value_t::string>::construct(j, std::move(s));
-}
-
-template<typename BasicJsonType, typename FloatType,
- enable_if_t<std::is_floating_point<FloatType>::value, int> = 0>
-void to_json(BasicJsonType& j, FloatType val) noexcept
-{
- external_constructor<value_t::number_float>::construct(j, static_cast<typename BasicJsonType::number_float_t>(val));
-}
-
-template<typename BasicJsonType, typename CompatibleNumberUnsignedType,
- enable_if_t<is_compatible_integer_type<typename BasicJsonType::number_unsigned_t, CompatibleNumberUnsignedType>::value, int> = 0>
-void to_json(BasicJsonType& j, CompatibleNumberUnsignedType val) noexcept
-{
- external_constructor<value_t::number_unsigned>::construct(j, static_cast<typename BasicJsonType::number_unsigned_t>(val));
-}
-
-template<typename BasicJsonType, typename CompatibleNumberIntegerType,
- enable_if_t<is_compatible_integer_type<typename BasicJsonType::number_integer_t, CompatibleNumberIntegerType>::value, int> = 0>
-void to_json(BasicJsonType& j, CompatibleNumberIntegerType val) noexcept
-{
- external_constructor<value_t::number_integer>::construct(j, static_cast<typename BasicJsonType::number_integer_t>(val));
-}
-
-template<typename BasicJsonType, typename EnumType,
- enable_if_t<std::is_enum<EnumType>::value, int> = 0>
-void to_json(BasicJsonType& j, EnumType e) noexcept
-{
- using underlying_type = typename std::underlying_type<EnumType>::type;
- external_constructor<value_t::number_integer>::construct(j, static_cast<underlying_type>(e));
-}
-
-template<typename BasicJsonType>
-void to_json(BasicJsonType& j, const std::vector<bool>& e)
-{
- external_constructor<value_t::array>::construct(j, e);
-}
-
-template <typename BasicJsonType, typename CompatibleArrayType,
- enable_if_t<is_compatible_array_type<BasicJsonType,
- CompatibleArrayType>::value and
- not is_compatible_object_type<
- BasicJsonType, CompatibleArrayType>::value and
- not is_compatible_string_type<BasicJsonType, CompatibleArrayType>::value and
- not is_basic_json<CompatibleArrayType>::value,
- int> = 0>
-void to_json(BasicJsonType& j, const CompatibleArrayType& arr)
-{
- external_constructor<value_t::array>::construct(j, arr);
-}
-
-template<typename BasicJsonType, typename T,
- enable_if_t<std::is_convertible<T, BasicJsonType>::value, int> = 0>
-void to_json(BasicJsonType& j, const std::valarray<T>& arr)
-{
- external_constructor<value_t::array>::construct(j, std::move(arr));
-}
-
-template<typename BasicJsonType>
-void to_json(BasicJsonType& j, typename BasicJsonType::array_t&& arr)
-{
- external_constructor<value_t::array>::construct(j, std::move(arr));
-}
-
-template<typename BasicJsonType, typename CompatibleObjectType,
- enable_if_t<is_compatible_object_type<BasicJsonType, CompatibleObjectType>::value and not is_basic_json<CompatibleObjectType>::value, int> = 0>
-void to_json(BasicJsonType& j, const CompatibleObjectType& obj)
-{
- external_constructor<value_t::object>::construct(j, obj);
-}
-
-template<typename BasicJsonType>
-void to_json(BasicJsonType& j, typename BasicJsonType::object_t&& obj)
-{
- external_constructor<value_t::object>::construct(j, std::move(obj));
-}
-
-template <
- typename BasicJsonType, typename T, std::size_t N,
- enable_if_t<not std::is_constructible<typename BasicJsonType::string_t,
- const T (&)[N]>::value,
- int> = 0 >
-void to_json(BasicJsonType& j, const T (&arr)[N])
-{
- external_constructor<value_t::array>::construct(j, arr);
-}
-
-template<typename BasicJsonType, typename... Args>
-void to_json(BasicJsonType& j, const std::pair<Args...>& p)
-{
- j = {p.first, p.second};
-}
-
-// for https://github.com/nlohmann/json/pull/1134
-template<typename BasicJsonType, typename T,
- enable_if_t<std::is_same<T, typename iteration_proxy<typename BasicJsonType::iterator>::iteration_proxy_internal>::value, int> = 0>
-void to_json(BasicJsonType& j, const T& b)
-{
- j = {{b.key(), b.value()}};
-}
-
-template<typename BasicJsonType, typename Tuple, std::size_t... Idx>
-void to_json_tuple_impl(BasicJsonType& j, const Tuple& t, index_sequence<Idx...> /*unused*/)
-{
- j = {std::get<Idx>(t)...};
-}
-
-template<typename BasicJsonType, typename... Args>
-void to_json(BasicJsonType& j, const std::tuple<Args...>& t)
-{
- to_json_tuple_impl(j, t, index_sequence_for<Args...> {});
-}
-
-struct to_json_fn
-{
- template<typename BasicJsonType, typename T>
- auto operator()(BasicJsonType& j, T&& val) const noexcept(noexcept(to_json(j, std::forward<T>(val))))
- -> decltype(to_json(j, std::forward<T>(val)), void())
- {
- return to_json(j, std::forward<T>(val));
- }
-};
-} // namespace detail
-
-/// namespace to hold default `to_json` function
-namespace
-{
-constexpr const auto& to_json = detail::static_const<detail::to_json_fn>::value;
-} // namespace
-} // namespace nlohmann