move move number stringifying logic to symbolifier
This commit is contained in:
Kevin Xu
parent
125b0f4a6b
commit
8fb7f5b6e0
@ -21,6 +21,7 @@
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#include <nlohmann/detail/output/binary_writer.hpp>
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#include <nlohmann/detail/output/output_adapters.hpp>
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#include <nlohmann/detail/value_t.hpp>
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#include <nlohmann/detail/output/symbolifier.hpp>
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namespace nlohmann
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{
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@ -38,7 +39,7 @@ enum class error_handler_t
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ignore ///< ignore invalid UTF-8 sequences
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};
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template<typename BasicJsonType>
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template<typename BasicJsonType, typename SymbolifierType = symbolifier>
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class serializer
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{
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using string_t = typename BasicJsonType::string_t;
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@ -58,9 +59,6 @@ class serializer
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serializer(output_adapter_t<char> s, const char ichar,
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error_handler_t error_handler_ = error_handler_t::strict)
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: o(std::move(s))
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, loc(std::localeconv())
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, thousands_sep(loc->thousands_sep == nullptr ? '\0' : std::char_traits<char>::to_char_type(* (loc->thousands_sep)))
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, decimal_point(loc->decimal_point == nullptr ? '\0' : std::char_traits<char>::to_char_type(* (loc->decimal_point)))
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, indent_char(ichar)
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, indent_string(512, indent_char)
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, error_handler(error_handler_)
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@ -265,10 +263,10 @@ class serializer
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for (auto i = val.m_value.binary->cbegin();
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i != val.m_value.binary->cend() - 1; ++i)
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{
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dump_integer(*i);
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SymbolifierType::dump_integer(o, *i);
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o->write_characters(", ", 2);
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}
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dump_integer(val.m_value.binary->back());
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SymbolifierType::dump_integer(o, val.m_value.binary->back());
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}
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o->write_characters("],\n", 3);
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@ -277,7 +275,7 @@ class serializer
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o->write_characters("\"subtype\": ", 11);
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if (val.m_value.binary->has_subtype())
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{
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dump_integer(val.m_value.binary->subtype());
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SymbolifierType::dump_integer(o, val.m_value.binary->subtype());
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}
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else
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{
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@ -296,16 +294,16 @@ class serializer
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for (auto i = val.m_value.binary->cbegin();
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i != val.m_value.binary->cend() - 1; ++i)
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{
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dump_integer(*i);
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SymbolifierType::dump_integer(o, *i);
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o->write_character(',');
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}
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dump_integer(val.m_value.binary->back());
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SymbolifierType::dump_integer(o, val.m_value.binary->back());
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}
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o->write_characters("],\"subtype\":", 12);
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if (val.m_value.binary->has_subtype())
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{
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dump_integer(val.m_value.binary->subtype());
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SymbolifierType::dump_integer(o, val.m_value.binary->subtype());
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o->write_character('}');
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}
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else
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@ -331,19 +329,19 @@ class serializer
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case value_t::number_integer:
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{
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dump_integer(val.m_value.number_integer);
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SymbolifierType::dump_integer(o, val.m_value.number_integer);
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return;
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}
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case value_t::number_unsigned:
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{
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dump_integer(val.m_value.number_unsigned);
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SymbolifierType::dump_integer(o, val.m_value.number_unsigned);
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return;
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}
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case value_t::number_float:
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{
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dump_float(val.m_value.number_float);
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SymbolifierType::dump_float(o, val.m_value.number_float);
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return;
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}
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@ -630,220 +628,6 @@ class serializer
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}
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private:
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/*!
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@brief count digits
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Count the number of decimal (base 10) digits for an input unsigned integer.
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@param[in] x unsigned integer number to count its digits
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@return number of decimal digits
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*/
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inline unsigned int count_digits(number_unsigned_t x) noexcept
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{
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unsigned int n_digits = 1;
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for (;;)
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{
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if (x < 10)
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{
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return n_digits;
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}
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if (x < 100)
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{
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return n_digits + 1;
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}
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if (x < 1000)
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{
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return n_digits + 2;
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}
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if (x < 10000)
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{
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return n_digits + 3;
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}
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x = x / 10000u;
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n_digits += 4;
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}
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}
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/*!
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@brief dump an integer
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Dump a given integer to output stream @a o. Works internally with
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@a number_buffer.
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@param[in] x integer number (signed or unsigned) to dump
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@tparam NumberType either @a number_integer_t or @a number_unsigned_t
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*/
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template < typename NumberType, detail::enable_if_t <
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std::is_integral<NumberType>::value ||
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std::is_same<NumberType, number_unsigned_t>::value ||
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std::is_same<NumberType, number_integer_t>::value ||
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std::is_same<NumberType, binary_char_t>::value,
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int > = 0 >
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void dump_integer(NumberType x)
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{
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static constexpr std::array<std::array<char, 2>, 100> digits_to_99
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{
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{
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{{'0', '0'}}, {{'0', '1'}}, {{'0', '2'}}, {{'0', '3'}}, {{'0', '4'}}, {{'0', '5'}}, {{'0', '6'}}, {{'0', '7'}}, {{'0', '8'}}, {{'0', '9'}},
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{{'1', '0'}}, {{'1', '1'}}, {{'1', '2'}}, {{'1', '3'}}, {{'1', '4'}}, {{'1', '5'}}, {{'1', '6'}}, {{'1', '7'}}, {{'1', '8'}}, {{'1', '9'}},
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{{'2', '0'}}, {{'2', '1'}}, {{'2', '2'}}, {{'2', '3'}}, {{'2', '4'}}, {{'2', '5'}}, {{'2', '6'}}, {{'2', '7'}}, {{'2', '8'}}, {{'2', '9'}},
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{{'3', '0'}}, {{'3', '1'}}, {{'3', '2'}}, {{'3', '3'}}, {{'3', '4'}}, {{'3', '5'}}, {{'3', '6'}}, {{'3', '7'}}, {{'3', '8'}}, {{'3', '9'}},
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{{'4', '0'}}, {{'4', '1'}}, {{'4', '2'}}, {{'4', '3'}}, {{'4', '4'}}, {{'4', '5'}}, {{'4', '6'}}, {{'4', '7'}}, {{'4', '8'}}, {{'4', '9'}},
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{{'5', '0'}}, {{'5', '1'}}, {{'5', '2'}}, {{'5', '3'}}, {{'5', '4'}}, {{'5', '5'}}, {{'5', '6'}}, {{'5', '7'}}, {{'5', '8'}}, {{'5', '9'}},
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{{'6', '0'}}, {{'6', '1'}}, {{'6', '2'}}, {{'6', '3'}}, {{'6', '4'}}, {{'6', '5'}}, {{'6', '6'}}, {{'6', '7'}}, {{'6', '8'}}, {{'6', '9'}},
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{{'7', '0'}}, {{'7', '1'}}, {{'7', '2'}}, {{'7', '3'}}, {{'7', '4'}}, {{'7', '5'}}, {{'7', '6'}}, {{'7', '7'}}, {{'7', '8'}}, {{'7', '9'}},
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{{'8', '0'}}, {{'8', '1'}}, {{'8', '2'}}, {{'8', '3'}}, {{'8', '4'}}, {{'8', '5'}}, {{'8', '6'}}, {{'8', '7'}}, {{'8', '8'}}, {{'8', '9'}},
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{{'9', '0'}}, {{'9', '1'}}, {{'9', '2'}}, {{'9', '3'}}, {{'9', '4'}}, {{'9', '5'}}, {{'9', '6'}}, {{'9', '7'}}, {{'9', '8'}}, {{'9', '9'}},
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}
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};
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// special case for "0"
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if (x == 0)
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{
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o->write_character('0');
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return;
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}
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// use a pointer to fill the buffer
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auto buffer_ptr = number_buffer.begin(); // NOLINT(llvm-qualified-auto,readability-qualified-auto,cppcoreguidelines-pro-type-vararg,hicpp-vararg)
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const bool is_negative = std::is_signed<NumberType>::value && !(x >= 0); // see issue #755
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number_unsigned_t abs_value;
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unsigned int n_chars{};
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if (is_negative)
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{
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*buffer_ptr = '-';
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abs_value = remove_sign(static_cast<number_integer_t>(x));
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// account one more byte for the minus sign
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n_chars = 1 + count_digits(abs_value);
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}
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else
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{
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abs_value = static_cast<number_unsigned_t>(x);
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n_chars = count_digits(abs_value);
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}
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// spare 1 byte for '\0'
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JSON_ASSERT(n_chars < number_buffer.size() - 1);
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// jump to the end to generate the string from backward
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// so we later avoid reversing the result
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buffer_ptr += n_chars;
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// Fast int2ascii implementation inspired by "Fastware" talk by Andrei Alexandrescu
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// See: https://www.youtube.com/watch?v=o4-CwDo2zpg
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while (abs_value >= 100)
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{
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const auto digits_index = static_cast<unsigned>((abs_value % 100));
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abs_value /= 100;
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*(--buffer_ptr) = digits_to_99[digits_index][1];
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*(--buffer_ptr) = digits_to_99[digits_index][0];
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}
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if (abs_value >= 10)
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{
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const auto digits_index = static_cast<unsigned>(abs_value);
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*(--buffer_ptr) = digits_to_99[digits_index][1];
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*(--buffer_ptr) = digits_to_99[digits_index][0];
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}
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else
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{
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*(--buffer_ptr) = static_cast<char>('0' + abs_value);
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}
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o->write_characters(number_buffer.data(), n_chars);
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}
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/*!
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@brief dump a floating-point number
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Dump a given floating-point number to output stream @a o. Works internally
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with @a number_buffer.
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@param[in] x floating-point number to dump
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*/
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void dump_float(number_float_t x)
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{
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// NaN / inf
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if (!std::isfinite(x))
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{
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o->write_characters("null", 4);
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return;
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}
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// If number_float_t is an IEEE-754 single or double precision number,
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// use the Grisu2 algorithm to produce short numbers which are
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// guaranteed to round-trip, using strtof and strtod, resp.
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//
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// NB: The test below works if <long double> == <double>.
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static constexpr bool is_ieee_single_or_double
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= (std::numeric_limits<number_float_t>::is_iec559 && std::numeric_limits<number_float_t>::digits == 24 && std::numeric_limits<number_float_t>::max_exponent == 128) ||
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(std::numeric_limits<number_float_t>::is_iec559 && std::numeric_limits<number_float_t>::digits == 53 && std::numeric_limits<number_float_t>::max_exponent == 1024);
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dump_float(x, std::integral_constant<bool, is_ieee_single_or_double>());
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}
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void dump_float(number_float_t x, std::true_type /*is_ieee_single_or_double*/)
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{
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auto* begin = number_buffer.data();
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auto* end = ::nlohmann::detail::to_chars(begin, begin + number_buffer.size(), x);
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o->write_characters(begin, static_cast<size_t>(end - begin));
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}
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void dump_float(number_float_t x, std::false_type /*is_ieee_single_or_double*/)
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{
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// get number of digits for a float -> text -> float round-trip
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static constexpr auto d = std::numeric_limits<number_float_t>::max_digits10;
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// the actual conversion
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// NOLINTNEXTLINE(cppcoreguidelines-pro-type-vararg,hicpp-vararg)
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std::ptrdiff_t len = (std::snprintf)(number_buffer.data(), number_buffer.size(), "%.*g", d, x);
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// negative value indicates an error
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JSON_ASSERT(len > 0);
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// check if buffer was large enough
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JSON_ASSERT(static_cast<std::size_t>(len) < number_buffer.size());
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// erase thousands separator
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if (thousands_sep != '\0')
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{
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// NOLINTNEXTLINE(readability-qualified-auto,llvm-qualified-auto): std::remove returns an iterator, see https://github.com/nlohmann/json/issues/3081
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const auto end = std::remove(number_buffer.begin(), number_buffer.begin() + len, thousands_sep);
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std::fill(end, number_buffer.end(), '\0');
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JSON_ASSERT((end - number_buffer.begin()) <= len);
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len = (end - number_buffer.begin());
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}
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// convert decimal point to '.'
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if (decimal_point != '\0' && decimal_point != '.')
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{
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// NOLINTNEXTLINE(readability-qualified-auto,llvm-qualified-auto): std::find returns an iterator, see https://github.com/nlohmann/json/issues/3081
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const auto dec_pos = std::find(number_buffer.begin(), number_buffer.end(), decimal_point);
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if (dec_pos != number_buffer.end())
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{
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*dec_pos = '.';
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}
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}
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o->write_characters(number_buffer.data(), static_cast<std::size_t>(len));
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// determine if need to append ".0"
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const bool value_is_int_like =
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std::none_of(number_buffer.begin(), number_buffer.begin() + len + 1,
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[](char c)
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{
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return c == '.' || c == 'e';
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});
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if (value_is_int_like)
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{
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o->write_characters(".0", 2);
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}
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}
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/*!
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@brief check whether a string is UTF-8 encoded
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@ -901,46 +685,10 @@ class serializer
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return state;
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}
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/*
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* Overload to make the compiler happy while it is instantiating
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* dump_integer for number_unsigned_t.
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* Must never be called.
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*/
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number_unsigned_t remove_sign(number_unsigned_t x)
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{
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JSON_ASSERT(false); // NOLINT(cert-dcl03-c,hicpp-static-assert,misc-static-assert) LCOV_EXCL_LINE
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return x; // LCOV_EXCL_LINE
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}
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/*
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* Helper function for dump_integer
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*
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* This function takes a negative signed integer and returns its absolute
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* value as unsigned integer. The plus/minus shuffling is necessary as we can
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* not directly remove the sign of an arbitrary signed integer as the
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* absolute values of INT_MIN and INT_MAX are usually not the same. See
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* #1708 for details.
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*/
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inline number_unsigned_t remove_sign(number_integer_t x) noexcept
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{
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JSON_ASSERT(x < 0 && x < (std::numeric_limits<number_integer_t>::max)()); // NOLINT(misc-redundant-expression)
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return static_cast<number_unsigned_t>(-(x + 1)) + 1;
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}
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private:
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/// the output of the serializer
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output_adapter_t<char> o = nullptr;
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/// a (hopefully) large enough character buffer
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std::array<char, 64> number_buffer{{}};
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/// the locale
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const std::lconv* loc = nullptr;
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/// the locale's thousand separator character
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const char thousands_sep = '\0';
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/// the locale's decimal point character
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const char decimal_point = '\0';
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/// string buffer
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std::array<char, 512> string_buffer{{}};
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247
include/nlohmann/detail/output/symbolifier.hpp
Normal file
247
include/nlohmann/detail/output/symbolifier.hpp
Normal file
@ -0,0 +1,247 @@
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#include <algorithm> // reverse, remove, fill, find, none_of
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#include <array> // array
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#include <clocale> // localeconv, lconv
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#include <cmath> // labs, isfinite, isnan, signbit
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#include <cstddef> // size_t, ptrdiff_t
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#include <cstdint> // uint8_t
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#include <cstdio> // snprintf
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#include <limits> // numeric_limits
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#include <string> // string, char_traits
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#include <iomanip> // setfill, setw
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#include <sstream> // stringstream
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#include <type_traits> // is_same
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#include <utility> // move
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namespace nlohmann
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{
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namespace detail
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{
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struct symbolifier
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{
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using number_buffer_t = std::array<char, 64>;
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template <typename number_unsigned_t>
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static unsigned int count_digits(number_unsigned_t x) noexcept
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{
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unsigned int n_digits = 1;
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for (;;)
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{
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if (x < 10)
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{
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return n_digits;
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}
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if (x < 100)
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{
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return n_digits + 1;
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}
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if (x < 1000)
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{
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return n_digits + 2;
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}
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if (x < 10000)
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{
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return n_digits + 3;
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}
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x = x / 10000u;
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n_digits += 4;
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}
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}
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template <typename number_integral_t, typename number_unsigned_t =
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typename std::make_unsigned<
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number_integral_t>::type>
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static number_unsigned_t remove_sign(number_integral_t x) noexcept
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{
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JSON_ASSERT(x < 0 && x < (std::numeric_limits<number_integral_t>::max)()); // NOLINT(misc-redundant-expression)
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return static_cast<number_unsigned_t>(-(x + 1)) + 1;
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}
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template <typename OutputAdapterType, typename number_integral_t,
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typename number_unsigned_t = typename std::make_unsigned<
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number_integral_t>::type>
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static void dump_integer(OutputAdapterType& o, number_integral_t x)
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{
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static constexpr std::array<std::array<char, 2>, 100> digits_to_99
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||||
{
|
||||
{
|
||||
{{'0', '0'}}, {{'0', '1'}}, {{'0', '2'}}, {{'0', '3'}}, {{'0', '4'}}, {{'0', '5'}}, {{'0', '6'}}, {{'0', '7'}}, {{'0', '8'}}, {{'0', '9'}},
|
||||
{{'1', '0'}}, {{'1', '1'}}, {{'1', '2'}}, {{'1', '3'}}, {{'1', '4'}}, {{'1', '5'}}, {{'1', '6'}}, {{'1', '7'}}, {{'1', '8'}}, {{'1', '9'}},
|
||||
{{'2', '0'}}, {{'2', '1'}}, {{'2', '2'}}, {{'2', '3'}}, {{'2', '4'}}, {{'2', '5'}}, {{'2', '6'}}, {{'2', '7'}}, {{'2', '8'}}, {{'2', '9'}},
|
||||
{{'3', '0'}}, {{'3', '1'}}, {{'3', '2'}}, {{'3', '3'}}, {{'3', '4'}}, {{'3', '5'}}, {{'3', '6'}}, {{'3', '7'}}, {{'3', '8'}}, {{'3', '9'}},
|
||||
{{'4', '0'}}, {{'4', '1'}}, {{'4', '2'}}, {{'4', '3'}}, {{'4', '4'}}, {{'4', '5'}}, {{'4', '6'}}, {{'4', '7'}}, {{'4', '8'}}, {{'4', '9'}},
|
||||
{{'5', '0'}}, {{'5', '1'}}, {{'5', '2'}}, {{'5', '3'}}, {{'5', '4'}}, {{'5', '5'}}, {{'5', '6'}}, {{'5', '7'}}, {{'5', '8'}}, {{'5', '9'}},
|
||||
{{'6', '0'}}, {{'6', '1'}}, {{'6', '2'}}, {{'6', '3'}}, {{'6', '4'}}, {{'6', '5'}}, {{'6', '6'}}, {{'6', '7'}}, {{'6', '8'}}, {{'6', '9'}},
|
||||
{{'7', '0'}}, {{'7', '1'}}, {{'7', '2'}}, {{'7', '3'}}, {{'7', '4'}}, {{'7', '5'}}, {{'7', '6'}}, {{'7', '7'}}, {{'7', '8'}}, {{'7', '9'}},
|
||||
{{'8', '0'}}, {{'8', '1'}}, {{'8', '2'}}, {{'8', '3'}}, {{'8', '4'}}, {{'8', '5'}}, {{'8', '6'}}, {{'8', '7'}}, {{'8', '8'}}, {{'8', '9'}},
|
||||
{{'9', '0'}}, {{'9', '1'}}, {{'9', '2'}}, {{'9', '3'}}, {{'9', '4'}}, {{'9', '5'}}, {{'9', '6'}}, {{'9', '7'}}, {{'9', '8'}}, {{'9', '9'}},
|
||||
}
|
||||
};
|
||||
|
||||
// special case for "0"
|
||||
if (x == 0)
|
||||
{
|
||||
o->write_character('0');
|
||||
return;
|
||||
}
|
||||
|
||||
number_buffer_t number_buffer{{}};
|
||||
|
||||
// use a pointer to fill the buffer
|
||||
auto buffer_ptr = number_buffer.begin(); // NOLINT(llvm-qualified-auto,readability-qualified-auto,cppcoreguidelines-pro-type-vararg,hicpp-vararg)
|
||||
|
||||
const bool is_negative = std::is_signed<number_integral_t>::value && !(x >= 0); // see issue #755
|
||||
number_unsigned_t abs_value;
|
||||
|
||||
unsigned int n_chars{};
|
||||
|
||||
if (is_negative)
|
||||
{
|
||||
*buffer_ptr = '-';
|
||||
abs_value = remove_sign(static_cast<number_integral_t>(x));
|
||||
|
||||
// account one more byte for the minus sign
|
||||
n_chars = 1 + count_digits(abs_value);
|
||||
}
|
||||
else
|
||||
{
|
||||
abs_value = static_cast<number_unsigned_t>(x);
|
||||
n_chars = count_digits(abs_value);
|
||||
}
|
||||
|
||||
// spare 1 byte for '\0'
|
||||
JSON_ASSERT(n_chars < number_buffer.size() - 1);
|
||||
|
||||
// jump to the end to generate the string from backward
|
||||
// so we later avoid reversing the result
|
||||
buffer_ptr += n_chars;
|
||||
|
||||
// Fast int2ascii implementation inspired by "Fastware" talk by Andrei Alexandrescu
|
||||
// See: https://www.youtube.com/watch?v=o4-CwDo2zpg
|
||||
while (abs_value >= 100)
|
||||
{
|
||||
const auto digits_index = static_cast<unsigned>((abs_value % 100));
|
||||
abs_value /= 100;
|
||||
*(--buffer_ptr) = digits_to_99[digits_index][1];
|
||||
*(--buffer_ptr) = digits_to_99[digits_index][0];
|
||||
}
|
||||
|
||||
if (abs_value >= 10)
|
||||
{
|
||||
const auto digits_index = static_cast<unsigned>(abs_value);
|
||||
*(--buffer_ptr) = digits_to_99[digits_index][1];
|
||||
*(--buffer_ptr) = digits_to_99[digits_index][0];
|
||||
}
|
||||
else
|
||||
{
|
||||
*(--buffer_ptr) = static_cast<char>('0' + abs_value);
|
||||
}
|
||||
|
||||
o->write_characters(number_buffer.data(), n_chars);
|
||||
}
|
||||
|
||||
|
||||
template <typename OutputAdapterType, typename number_float_t,
|
||||
detail::enable_if_t<
|
||||
std::is_floating_point<number_float_t>::value, int> = 0>
|
||||
static void dump_float(OutputAdapterType& o, number_float_t x)
|
||||
{
|
||||
// NaN / inf
|
||||
if (!std::isfinite(x))
|
||||
{
|
||||
o->write_characters("null", 4);
|
||||
return;
|
||||
}
|
||||
|
||||
// If number_float_t is an IEEE-754 single or double precision number,
|
||||
// use the Grisu2 algorithm to produce short numbers which are
|
||||
// guaranteed to round-trip, using strtof and strtod, resp.
|
||||
//
|
||||
// NB: The test below works if <long double> == <double>.
|
||||
static constexpr bool is_ieee_single_or_double
|
||||
= (std::numeric_limits<number_float_t>::is_iec559 && std::numeric_limits<number_float_t>::digits == 24 && std::numeric_limits<number_float_t>::max_exponent == 128) ||
|
||||
(std::numeric_limits<number_float_t>::is_iec559 && std::numeric_limits<number_float_t>::digits == 53 && std::numeric_limits<number_float_t>::max_exponent == 1024);
|
||||
|
||||
dump_float(o, x, std::integral_constant<bool, is_ieee_single_or_double>());
|
||||
}
|
||||
|
||||
template <typename OutputAdapterType, typename number_float_t,
|
||||
detail::enable_if_t<
|
||||
std::is_floating_point<number_float_t>::value, int> = 0>
|
||||
static void dump_float(OutputAdapterType& o, number_float_t x, std::true_type /*is_ieee_single_or_double*/)
|
||||
{
|
||||
number_buffer_t number_buffer{{}};
|
||||
|
||||
auto* begin = number_buffer.data();
|
||||
auto* end = ::nlohmann::detail::to_chars(begin, begin + number_buffer.size(), x);
|
||||
|
||||
o->write_characters(begin, static_cast<size_t>(end - begin));
|
||||
}
|
||||
|
||||
template <typename OutputAdapterType, typename number_float_t,
|
||||
detail::enable_if_t<
|
||||
std::is_floating_point<number_float_t>::value, int> = 0>
|
||||
static void dump_float(OutputAdapterType& o, number_float_t x, std::false_type /*is_ieee_single_or_double*/)
|
||||
{
|
||||
number_buffer_t number_buffer{{}};
|
||||
|
||||
const std::lconv* loc(std::localeconv());
|
||||
const char thousands_sep(loc->thousands_sep == nullptr ? '\0' : std::char_traits<char>::to_char_type(* (loc->thousands_sep)));
|
||||
const char decimal_point(loc->decimal_point == nullptr ? '\0' : std::char_traits<char>::to_char_type(* (loc->decimal_point)));
|
||||
|
||||
// get number of digits for a float -> text -> float round-trip
|
||||
static constexpr auto d = std::numeric_limits<number_float_t>::max_digits10;
|
||||
|
||||
// the actual conversion
|
||||
// NOLINTNEXTLINE(cppcoreguidelines-pro-type-vararg,hicpp-vararg)
|
||||
std::ptrdiff_t len = (std::snprintf)(number_buffer.data(), number_buffer.size(), "%.*g", d, x);
|
||||
|
||||
// negative value indicates an error
|
||||
JSON_ASSERT(len > 0);
|
||||
// check if buffer was large enough
|
||||
JSON_ASSERT(static_cast<std::size_t>(len) < number_buffer.size());
|
||||
|
||||
// erase thousands separator
|
||||
if (thousands_sep != '\0')
|
||||
{
|
||||
// NOLINTNEXTLINE(readability-qualified-auto,llvm-qualified-auto): std::remove returns an iterator, see https://github.com/nlohmann/json/issues/3081
|
||||
const auto end = std::remove(number_buffer.begin(), number_buffer.begin() + len, thousands_sep);
|
||||
std::fill(end, number_buffer.end(), '\0');
|
||||
JSON_ASSERT((end - number_buffer.begin()) <= len);
|
||||
len = (end - number_buffer.begin());
|
||||
}
|
||||
|
||||
// convert decimal point to '.'
|
||||
if (decimal_point != '\0' && decimal_point != '.')
|
||||
{
|
||||
// NOLINTNEXTLINE(readability-qualified-auto,llvm-qualified-auto): std::find returns an iterator, see https://github.com/nlohmann/json/issues/3081
|
||||
const auto dec_pos = std::find(number_buffer.begin(), number_buffer.end(), decimal_point);
|
||||
if (dec_pos != number_buffer.end())
|
||||
{
|
||||
*dec_pos = '.';
|
||||
}
|
||||
}
|
||||
|
||||
o->write_characters(number_buffer.data(), static_cast<std::size_t>(len));
|
||||
|
||||
// determine if need to append ".0"
|
||||
const bool value_is_int_like =
|
||||
std::none_of(number_buffer.begin(), number_buffer.begin() + len + 1,
|
||||
[](char c)
|
||||
{
|
||||
return c == '.' || c == 'e';
|
||||
});
|
||||
|
||||
if (value_is_int_like)
|
||||
{
|
||||
o->write_characters(".0", 2);
|
||||
}
|
||||
}
|
||||
|
||||
};
|
||||
|
||||
}
|
||||
}
|
||||
@ -34,8 +34,13 @@ struct numerizer;
|
||||
template<typename BasicJsonType, typename InputAdapterType>
|
||||
using basic_lexer = lexer<BasicJsonType, InputAdapterType, numerizer>;
|
||||
|
||||
template<typename BasicJsonType>
|
||||
struct symbolifier;
|
||||
|
||||
template<typename BasicJsonType, typename SymbolifierType>
|
||||
class serializer;
|
||||
|
||||
template<typename BasicJsonType>
|
||||
using basic_serializer = serializer<BasicJsonType, symbolifier>;
|
||||
}
|
||||
|
||||
template<template<typename U, typename V, typename... Args> class ObjectType =
|
||||
@ -50,7 +55,7 @@ template<template<typename U, typename V, typename... Args> class ObjectType =
|
||||
adl_serializer,
|
||||
class BinaryType = std::vector<std::uint8_t>,
|
||||
template<typename BasicJsonType, typename InputAdapterType> class LexerType = detail::basic_lexer,
|
||||
template<typename BasicJsonType> class SerializerType = detail::serializer>
|
||||
template<typename BasicJsonType> class SerializerType = detail::basic_serializer>
|
||||
class basic_json;
|
||||
|
||||
/*!
|
||||
|
||||
Loading…
Reference in New Issue
Block a user