// Copyright 2012 the V8 project authors. All rights reserved.

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#ifndef DOUBLE_CONVERSION_DOUBLE_CONVERSION_H_

#define DOUBLE_CONVERSION_DOUBLE_CONVERSION_H_

#include "mozilla/Types.h"

#include <double-conversion/utils.h>

namespace double_conversion {

class DoubleToStringConverter {

 public:

  // When calling ToFixed with a double > 10^kMaxFixedDigitsBeforePoint

  // or a requested_digits parameter > kMaxFixedDigitsAfterPoint then the

  // function returns false.

  static const int kMaxFixedDigitsBeforePoint = 60;

  static const int kMaxFixedDigitsAfterPoint = 60;

  // When calling ToExponential with a requested_digits

  // parameter > kMaxExponentialDigits then the function returns false.

  static const int kMaxExponentialDigits = 120;

  // When calling ToPrecision with a requested_digits

  // parameter < kMinPrecisionDigits or requested_digits > kMaxPrecisionDigits

  // then the function returns false.

  static const int kMinPrecisionDigits = 1;

  static const int kMaxPrecisionDigits = 120;

  enum Flags {

    NO_FLAGS = 0,

    EMIT_POSITIVE_EXPONENT_SIGN = 1,

    EMIT_TRAILING_DECIMAL_POINT = 2,

    EMIT_TRAILING_ZERO_AFTER_POINT = 4,

    UNIQUE_ZERO = 8

  };

  // Flags should be a bit-or combination of the possible Flags-enum.

  //  - NO_FLAGS: no special flags.

  //  - EMIT_POSITIVE_EXPONENT_SIGN: when the number is converted into exponent

  //    form, emits a '+' for positive exponents. Example: 1.2e+2.

  //  - EMIT_TRAILING_DECIMAL_POINT: when the input number is an integer and is

  //    converted into decimal format then a trailing decimal point is appended.

  //    Example: 2345.0 is converted to "2345.".

  //  - EMIT_TRAILING_ZERO_AFTER_POINT: in addition to a trailing decimal point

  //    emits a trailing '0'-character. This flag requires the

  //    EXMIT_TRAILING_DECIMAL_POINT flag.

  //    Example: 2345.0 is converted to "2345.0".

  //  - UNIQUE_ZERO: "-0.0" is converted to "0.0".

  //

  // Infinity symbol and nan_symbol provide the string representation for these

  // special values. If the string is NULL and the special value is encountered

  // then the conversion functions return false.

  //

  // The exponent_character is used in exponential representations. It is

  // usually 'e' or 'E'.

  //

  // When converting to the shortest representation the converter will

  // represent input numbers in decimal format if they are in the interval

  // [10^decimal_in_shortest_low; 10^decimal_in_shortest_high[

  //    (lower boundary included, greater boundary excluded).

  // Example: with decimal_in_shortest_low = -6 and

  //               decimal_in_shortest_high = 21:

  //   ToShortest(0.000001)  -> "0.000001"

  //   ToShortest(0.0000001) -> "1e-7"

  //   ToShortest(111111111111111111111.0)  -> "111111111111111110000"

  //   ToShortest(100000000000000000000.0)  -> "100000000000000000000"

  //   ToShortest(1111111111111111111111.0) -> "1.1111111111111111e+21"

  //

  // When converting to precision mode the converter may add

  // max_leading_padding_zeroes before returning the number in exponential

  // format.

  // Example with max_leading_padding_zeroes_in_precision_mode = 6.

  //   ToPrecision(0.0000012345, 2) -> "0.0000012"

  //   ToPrecision(0.00000012345, 2) -> "1.2e-7"

  // Similarily the converter may add up to

  // max_trailing_padding_zeroes_in_precision_mode in precision mode to avoid

  // returning an exponential representation. A zero added by the

  // EMIT_TRAILING_ZERO_AFTER_POINT flag is counted for this limit.

  // Examples for max_trailing_padding_zeroes_in_precision_mode = 1:

  //   ToPrecision(230.0, 2) -> "230"

  //   ToPrecision(230.0, 2) -> "230."  with EMIT_TRAILING_DECIMAL_POINT.

  //   ToPrecision(230.0, 2) -> "2.3e2" with EMIT_TRAILING_ZERO_AFTER_POINT.

  DoubleToStringConverter(int flags,

                          const char* infinity_symbol,

                          const char* nan_symbol,

                          char exponent_character,

                          int decimal_in_shortest_low,

                          int decimal_in_shortest_high,

                          int max_leading_padding_zeroes_in_precision_mode,

                          int max_trailing_padding_zeroes_in_precision_mode)

      : flags_(flags),

        infinity_symbol_(infinity_symbol),

        nan_symbol_(nan_symbol),

        exponent_character_(exponent_character),

        decimal_in_shortest_low_(decimal_in_shortest_low),

        decimal_in_shortest_high_(decimal_in_shortest_high),

        max_leading_padding_zeroes_in_precision_mode_(

            max_leading_padding_zeroes_in_precision_mode),

        max_trailing_padding_zeroes_in_precision_mode_(

            max_trailing_padding_zeroes_in_precision_mode) {

    // When 'trailing zero after the point' is set, then 'trailing point'

    // must be set too.

    ASSERT(((flags & EMIT_TRAILING_DECIMAL_POINT) != 0) ||

        !((flags & EMIT_TRAILING_ZERO_AFTER_POINT) != 0));

  }

  // Returns a converter following the EcmaScript specification.

  static MFBT_API const DoubleToStringConverter& EcmaScriptConverter();

  // Computes the shortest string of digits that correctly represent the input

  // number. Depending on decimal_in_shortest_low and decimal_in_shortest_high

  // (see constructor) it then either returns a decimal representation, or an

  // exponential representation.

  // Example with decimal_in_shortest_low = -6,

  //              decimal_in_shortest_high = 21,

  //              EMIT_POSITIVE_EXPONENT_SIGN activated, and

  //              EMIT_TRAILING_DECIMAL_POINT deactived:

  //   ToShortest(0.000001)  -> "0.000001"

  //   ToShortest(0.0000001) -> "1e-7"

  //   ToShortest(111111111111111111111.0)  -> "111111111111111110000"

  //   ToShortest(100000000000000000000.0)  -> "100000000000000000000"

  //   ToShortest(1111111111111111111111.0) -> "1.1111111111111111e+21"

  //

  // Note: the conversion may round the output if the returned string

  // is accurate enough to uniquely identify the input-number.

  // For example the most precise representation of the double 9e59 equals

  // "899999999999999918767229449717619953810131273674690656206848", but

  // the converter will return the shorter (but still correct) "9e59".

  //

  // Returns true if the conversion succeeds. The conversion always succeeds

  // except when the input value is special and no infinity_symbol or

  // nan_symbol has been given to the constructor.

  bool ToShortest(double value, StringBuilder* result_builder) const {

    return ToShortestIeeeNumber(value, result_builder, SHORTEST);

  }

  // Same as ToShortest, but for single-precision floats.

  bool ToShortestSingle(float value, StringBuilder* result_builder) const {

    return ToShortestIeeeNumber(value, result_builder, SHORTEST_SINGLE);

  }

  // Computes a decimal representation with a fixed number of digits after the

  // decimal point. The last emitted digit is rounded.

  //

  // Examples:

  //   ToFixed(3.12, 1) -> "3.1"

  //   ToFixed(3.1415, 3) -> "3.142"

  //   ToFixed(1234.56789, 4) -> "1234.5679"

  //   ToFixed(1.23, 5) -> "1.23000"

  //   ToFixed(0.1, 4) -> "0.1000"

  //   ToFixed(1e30, 2) -> "1000000000000000019884624838656.00"

  //   ToFixed(0.1, 30) -> "0.100000000000000005551115123126"

  //   ToFixed(0.1, 17) -> "0.10000000000000001"

  //

  // If requested_digits equals 0, then the tail of the result depends on

  // the EMIT_TRAILING_DECIMAL_POINT and EMIT_TRAILING_ZERO_AFTER_POINT.

  // Examples, for requested_digits == 0,

  //   let EMIT_TRAILING_DECIMAL_POINT and EMIT_TRAILING_ZERO_AFTER_POINT be

  //    - false and false: then 123.45 -> 123

  //                             0.678 -> 1

  //    - true and false: then 123.45 -> 123.

  //                            0.678 -> 1.

  //    - true and true: then 123.45 -> 123.0

  //                           0.678 -> 1.0

  //

  // Returns true if the conversion succeeds. The conversion always succeeds

  // except for the following cases:

  //   - the input value is special and no infinity_symbol or nan_symbol has

  //     been provided to the constructor,

  //   - 'value' > 10^kMaxFixedDigitsBeforePoint, or

  //   - 'requested_digits' > kMaxFixedDigitsAfterPoint.

  // The last two conditions imply that the result will never contain more than

  // 1 + kMaxFixedDigitsBeforePoint + 1 + kMaxFixedDigitsAfterPoint characters

  // (one additional character for the sign, and one for the decimal point).

  MFBT_API bool ToFixed(double value,

               int requested_digits,

               StringBuilder* result_builder) const;

  // Computes a representation in exponential format with requested_digits

  // after the decimal point. The last emitted digit is rounded.

  // If requested_digits equals -1, then the shortest exponential representation

  // is computed.

  //

  // Examples with EMIT_POSITIVE_EXPONENT_SIGN deactivated, and

  //               exponent_character set to 'e'.

  //   ToExponential(3.12, 1) -> "3.1e0"

  //   ToExponential(5.0, 3) -> "5.000e0"

  //   ToExponential(0.001, 2) -> "1.00e-3"

  //   ToExponential(3.1415, -1) -> "3.1415e0"

  //   ToExponential(3.1415, 4) -> "3.1415e0"

  //   ToExponential(3.1415, 3) -> "3.142e0"

  //   ToExponential(123456789000000, 3) -> "1.235e14"

  //   ToExponential(1000000000000000019884624838656.0, -1) -> "1e30"

  //   ToExponential(1000000000000000019884624838656.0, 32) ->

  //                     "1.00000000000000001988462483865600e30"

  //   ToExponential(1234, 0) -> "1e3"

  //

  // Returns true if the conversion succeeds. The conversion always succeeds

  // except for the following cases:

  //   - the input value is special and no infinity_symbol or nan_symbol has

  //     been provided to the constructor,

  //   - 'requested_digits' > kMaxExponentialDigits.

  // The last condition implies that the result will never contain more than

  // kMaxExponentialDigits + 8 characters (the sign, the digit before the

  // decimal point, the decimal point, the exponent character, the

  // exponent's sign, and at most 3 exponent digits).

  MFBT_API bool ToExponential(double value,

                     int requested_digits,

                     StringBuilder* result_builder) const;

  // Computes 'precision' leading digits of the given 'value' and returns them

  // either in exponential or decimal format, depending on

  // max_{leading|trailing}_padding_zeroes_in_precision_mode (given to the

  // constructor).

  // The last computed digit is rounded.

  //

  // Example with max_leading_padding_zeroes_in_precision_mode = 6.

  //   ToPrecision(0.0000012345, 2) -> "0.0000012"

  //   ToPrecision(0.00000012345, 2) -> "1.2e-7"

  // Similarily the converter may add up to

  // max_trailing_padding_zeroes_in_precision_mode in precision mode to avoid

  // returning an exponential representation. A zero added by the

  // EMIT_TRAILING_ZERO_AFTER_POINT flag is counted for this limit.

  // Examples for max_trailing_padding_zeroes_in_precision_mode = 1:

  //   ToPrecision(230.0, 2) -> "230"

  //   ToPrecision(230.0, 2) -> "230."  with EMIT_TRAILING_DECIMAL_POINT.

  //   ToPrecision(230.0, 2) -> "2.3e2" with EMIT_TRAILING_ZERO_AFTER_POINT.

  // Examples for max_trailing_padding_zeroes_in_precision_mode = 3, and no

  //    EMIT_TRAILING_ZERO_AFTER_POINT:

  //   ToPrecision(123450.0, 6) -> "123450"

  //   ToPrecision(123450.0, 5) -> "123450"

  //   ToPrecision(123450.0, 4) -> "123500"

  //   ToPrecision(123450.0, 3) -> "123000"

  //   ToPrecision(123450.0, 2) -> "1.2e5"

  //

  // Returns true if the conversion succeeds. The conversion always succeeds

  // except for the following cases:

  //   - the input value is special and no infinity_symbol or nan_symbol has

  //     been provided to the constructor,

  //   - precision < kMinPericisionDigits

  //   - precision > kMaxPrecisionDigits

  // The last condition implies that the result will never contain more than

  // kMaxPrecisionDigits + 7 characters (the sign, the decimal point, the

  // exponent character, the exponent's sign, and at most 3 exponent digits).

  MFBT_API bool ToPrecision(double value,

                   int precision,

                   bool* used_exponential_notation,

                   StringBuilder* result_builder) const;

  enum DtoaMode {

    // Produce the shortest correct representation.

    // For example the output of 0.299999999999999988897 is (the less accurate

    // but correct) 0.3.

    SHORTEST,

    // Same as SHORTEST, but for single-precision floats.

    SHORTEST_SINGLE,

    // Produce a fixed number of digits after the decimal point.

    // For instance fixed(0.1, 4) becomes 0.1000

    // If the input number is big, the output will be big.

    FIXED,

    // Fixed number of digits (independent of the decimal point).

    PRECISION

  };

  // The maximal number of digits that are needed to emit a double in base 10.

  // A higher precision can be achieved by using more digits, but the shortest

  // accurate representation of any double will never use more digits than

  // kBase10MaximalLength.

  // Note that DoubleToAscii null-terminates its input. So the given buffer

  // should be at least kBase10MaximalLength + 1 characters long.

  static const MFBT_DATA int kBase10MaximalLength = 17;

  // Converts the given double 'v' to digit characters. 'v' must not be NaN,

  // +Infinity, or -Infinity. In SHORTEST_SINGLE-mode this restriction also

  // applies to 'v' after it has been casted to a single-precision float. That

  // is, in this mode static_cast<float>(v) must not be NaN, +Infinity or

  // -Infinity.

  //

  // The result should be interpreted as buffer * 10^(point-length).

  //

  // The digits are written to the buffer in the platform's charset, which is

  // often UTF-8 (with ASCII-range digits) but may be another charset, such

  // as EBCDIC.

  //

  // The output depends on the given mode:

  //  - SHORTEST: produce the least amount of digits for which the internal

  //   identity requirement is still satisfied. If the digits are printed

  //   (together with the correct exponent) then reading this number will give

  //   'v' again. The buffer will choose the representation that is closest to

  //   'v'. If there are two at the same distance, than the one farther away

  //   from 0 is chosen (halfway cases - ending with 5 - are rounded up).

  //   In this mode the 'requested_digits' parameter is ignored.

  //  - SHORTEST_SINGLE: same as SHORTEST but with single-precision.

  //  - FIXED: produces digits necessary to print a given number with

  //   'requested_digits' digits after the decimal point. The produced digits

  //   might be too short in which case the caller has to fill the remainder

  //   with '0's.

  //   Example: toFixed(0.001, 5) is allowed to return buffer="1", point=-2.

  //   Halfway cases are rounded towards +/-Infinity (away from 0). The call

  //   toFixed(0.15, 2) thus returns buffer="2", point=0.

  //   The returned buffer may contain digits that would be truncated from the

  //   shortest representation of the input.

  //  - PRECISION: produces 'requested_digits' where the first digit is not '0'.

  //   Even though the length of produced digits usually equals

  //   'requested_digits', the function is allowed to return fewer digits, in

  //   which case the caller has to fill the missing digits with '0's.

  //   Halfway cases are again rounded away from 0.

  // DoubleToAscii expects the given buffer to be big enough to hold all

  // digits and a terminating null-character. In SHORTEST-mode it expects a

  // buffer of at least kBase10MaximalLength + 1. In all other modes the

  // requested_digits parameter and the padding-zeroes limit the size of the

  // output. Don't forget the decimal point, the exponent character and the

  // terminating null-character when computing the maximal output size.

  // The given length is only used in debug mode to ensure the buffer is big

  // enough.

  static MFBT_API void DoubleToAscii(double v,

                            DtoaMode mode,

                            int requested_digits,

                            char* buffer,

                            int buffer_length,

                            bool* sign,

                            int* length,

                            int* point);

 private:

  // Implementation for ToShortest and ToShortestSingle.

  MFBT_API bool ToShortestIeeeNumber(double value,

                            StringBuilder* result_builder,

                            DtoaMode mode) const;

  // If the value is a special value (NaN or Infinity) constructs the

  // corresponding string using the configured infinity/nan-symbol.

  // If either of them is NULL or the value is not special then the

  // function returns false.

  MFBT_API bool HandleSpecialValues(double value, StringBuilder* result_builder) const;

  // Constructs an exponential representation (i.e. 1.234e56).

  // The given exponent assumes a decimal point after the first decimal digit.

  MFBT_API void CreateExponentialRepresentation(const char* decimal_digits,

                                       int length,

                                       int exponent,

                                       StringBuilder* result_builder) const;

  // Creates a decimal representation (i.e 1234.5678).

  MFBT_API void CreateDecimalRepresentation(const char* decimal_digits,

                                   int length,

                                   int decimal_point,

                                   int digits_after_point,

                                   StringBuilder* result_builder) const;

  const int flags_;

  const char* const infinity_symbol_;

  const char* const nan_symbol_;

  const char exponent_character_;

  const int decimal_in_shortest_low_;

  const int decimal_in_shortest_high_;

  const int max_leading_padding_zeroes_in_precision_mode_;

  const int max_trailing_padding_zeroes_in_precision_mode_;

  DC_DISALLOW_IMPLICIT_CONSTRUCTORS(DoubleToStringConverter);

};

class StringToDoubleConverter {

 public:

  // Enumeration for allowing octals and ignoring junk when converting

  // strings to numbers.

  enum Flags {

    NO_FLAGS = 0,

    ALLOW_HEX = 1,

    ALLOW_OCTALS = 2,

    ALLOW_TRAILING_JUNK = 4,

    ALLOW_LEADING_SPACES = 8,

    ALLOW_TRAILING_SPACES = 16,

    ALLOW_SPACES_AFTER_SIGN = 32,

    ALLOW_CASE_INSENSIBILITY = 64,

  };

  // Flags should be a bit-or combination of the possible Flags-enum.

  //  - NO_FLAGS: no special flags.

  //  - ALLOW_HEX: recognizes the prefix "0x". Hex numbers may only be integers.

  //      Ex: StringToDouble("0x1234") -> 4660.0

  //          In StringToDouble("0x1234.56") the characters ".56" are trailing

  //          junk. The result of the call is hence dependent on

  //          the ALLOW_TRAILING_JUNK flag and/or the junk value.

  //      With this flag "0x" is a junk-string. Even with ALLOW_TRAILING_JUNK,

  //      the string will not be parsed as "0" followed by junk.

  //

  //  - ALLOW_OCTALS: recognizes the prefix "0" for octals:

  //      If a sequence of octal digits starts with '0', then the number is

  //      read as octal integer. Octal numbers may only be integers.

  //      Ex: StringToDouble("01234") -> 668.0

  //          StringToDouble("012349") -> 12349.0  // Not a sequence of octal

  //                                               // digits.

  //          In StringToDouble("01234.56") the characters ".56" are trailing

  //          junk. The result of the call is hence dependent on

  //          the ALLOW_TRAILING_JUNK flag and/or the junk value.

  //          In StringToDouble("01234e56") the characters "e56" are trailing

  //          junk, too.

  //  - ALLOW_TRAILING_JUNK: ignore trailing characters that are not part of

  //      a double literal.

  //  - ALLOW_LEADING_SPACES: skip over leading whitespace, including spaces,

  //                          new-lines, and tabs.

  //  - ALLOW_TRAILING_SPACES: ignore trailing whitespace.

  //  - ALLOW_SPACES_AFTER_SIGN: ignore whitespace after the sign.

  //       Ex: StringToDouble("-   123.2") -> -123.2.

  //           StringToDouble("+   123.2") -> 123.2

  //  - ALLOW_CASE_INSENSIBILITY: ignore case of characters for special values:

  //      infinity and nan.

  //

  // empty_string_value is returned when an empty string is given as input.

  // If ALLOW_LEADING_SPACES or ALLOW_TRAILING_SPACES are set, then a string

  // containing only spaces is converted to the 'empty_string_value', too.

  //

  // junk_string_value is returned when

  //  a) ALLOW_TRAILING_JUNK is not set, and a junk character (a character not

  //     part of a double-literal) is found.

  //  b) ALLOW_TRAILING_JUNK is set, but the string does not start with a

  //     double literal.

  //

  // infinity_symbol and nan_symbol are strings that are used to detect

  // inputs that represent infinity and NaN. They can be null, in which case

  // they are ignored.

  // The conversion routine first reads any possible signs. Then it compares the

  // following character of the input-string with the first character of

  // the infinity, and nan-symbol. If either matches, the function assumes, that

  // a match has been found, and expects the following input characters to match

  // the remaining characters of the special-value symbol.

  // This means that the following restrictions apply to special-value symbols:

  //  - they must not start with signs ('+', or '-'),

  //  - they must not have the same first character.

  //  - they must not start with digits.

  //

  // Examples:

  //  flags = ALLOW_HEX | ALLOW_TRAILING_JUNK,

  //  empty_string_value = 0.0,

  //  junk_string_value = NaN,

  //  infinity_symbol = "infinity",

  //  nan_symbol = "nan":

  //    StringToDouble("0x1234") -> 4660.0.

  //    StringToDouble("0x1234K") -> 4660.0.

  //    StringToDouble("") -> 0.0  // empty_string_value.

  //    StringToDouble(" ") -> NaN  // junk_string_value.

  //    StringToDouble(" 1") -> NaN  // junk_string_value.

  //    StringToDouble("0x") -> NaN  // junk_string_value.

  //    StringToDouble("-123.45") -> -123.45.

  //    StringToDouble("--123.45") -> NaN  // junk_string_value.

  //    StringToDouble("123e45") -> 123e45.

  //    StringToDouble("123E45") -> 123e45.

  //    StringToDouble("123e+45") -> 123e45.

  //    StringToDouble("123E-45") -> 123e-45.

  //    StringToDouble("123e") -> 123.0  // trailing junk ignored.

  //    StringToDouble("123e-") -> 123.0  // trailing junk ignored.

  //    StringToDouble("+NaN") -> NaN  // NaN string literal.

  //    StringToDouble("-infinity") -> -inf.  // infinity literal.

  //    StringToDouble("Infinity") -> NaN  // junk_string_value.

  //

  //  flags = ALLOW_OCTAL | ALLOW_LEADING_SPACES,

  //  empty_string_value = 0.0,

  //  junk_string_value = NaN,

  //  infinity_symbol = NULL,

  //  nan_symbol = NULL:

  //    StringToDouble("0x1234") -> NaN  // junk_string_value.

  //    StringToDouble("01234") -> 668.0.

  //    StringToDouble("") -> 0.0  // empty_string_value.

  //    StringToDouble(" ") -> 0.0  // empty_string_value.

  //    StringToDouble(" 1") -> 1.0

  //    StringToDouble("0x") -> NaN  // junk_string_value.

  //    StringToDouble("0123e45") -> NaN  // junk_string_value.

  //    StringToDouble("01239E45") -> 1239e45.

  //    StringToDouble("-infinity") -> NaN  // junk_string_value.

  //    StringToDouble("NaN") -> NaN  // junk_string_value.

  StringToDoubleConverter(int flags,

                          double empty_string_value,

                          double junk_string_value,

                          const char* infinity_symbol,

                          const char* nan_symbol)

      : flags_(flags),

        empty_string_value_(empty_string_value),

        junk_string_value_(junk_string_value),

        infinity_symbol_(infinity_symbol),

        nan_symbol_(nan_symbol) {

  }

  // Performs the conversion.

  // The output parameter 'processed_characters_count' is set to the number

  // of characters that have been processed to read the number.

  // Spaces than are processed with ALLOW_{LEADING|TRAILING}_SPACES are included

  // in the 'processed_characters_count'. Trailing junk is never included.

  double StringToDouble(const char* buffer,

                        int length,

                        int* processed_characters_count) const;

  // Same as StringToDouble above but for 16 bit characters.

  double StringToDouble(const uc16* buffer,

                        int length,

                        int* processed_characters_count) const;

  // Same as StringToDouble but reads a float.

  // Note that this is not equivalent to static_cast<float>(StringToDouble(...))

  // due to potential double-rounding.

  float StringToFloat(const char* buffer,

                      int length,

                      int* processed_characters_count) const;

  // Same as StringToFloat above but for 16 bit characters.

  float StringToFloat(const uc16* buffer,

                      int length,

                      int* processed_characters_count) const;

 private:

  const int flags_;

  const double empty_string_value_;

  const double junk_string_value_;

  const char* const infinity_symbol_;

  const char* const nan_symbol_;

  template <class Iterator>

  double StringToIeee(Iterator start_pointer,

                      int length,

                      bool read_as_double,

                      int* processed_characters_count) const;

  DC_DISALLOW_IMPLICIT_CONSTRUCTORS(StringToDoubleConverter);

};

}  // namespace double_conversion

#endif  // DOUBLE_CONVERSION_DOUBLE_CONVERSION_H_