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// © 2018 and later: Unicode, Inc. and others. 
// License & terms of use: http://www.unicode.org/copyright.html 
// 
// From the double-conversion library. Original license: 
// 
// Copyright 2012 the V8 project authors. All rights reserved. 
// Redistribution and use in source and binary forms, with or without 
// modification, are permitted provided that the following conditions are 
// met: 
// 
//     * Redistributions of source code must retain the above copyright 
//       notice, this list of conditions and the following disclaimer. 
//     * Redistributions in binary form must reproduce the above 
//       copyright notice, this list of conditions and the following 
//       disclaimer in the documentation and/or other materials provided 
//       with the distribution. 
//     * Neither the name of Google Inc. nor the names of its 
//       contributors may be used to endorse or promote products derived 
//       from this software without specific prior written permission. 
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
 
// ICU PATCH: ifdef around UCONFIG_NO_FORMATTING 
#include "unicode/utypes.h" 
#if !UCONFIG_NO_FORMATTING 
 
#ifndef DOUBLE_CONVERSION_STRING_TO_DOUBLE_H_ 
#define DOUBLE_CONVERSION_STRING_TO_DOUBLE_H_ 
 
// ICU PATCH: Customize header file paths for ICU. 
 
#include "double-conversion-utils.h" 
 
// ICU PATCH: Wrap in ICU namespace 
U_NAMESPACE_BEGIN 
 
namespace double_conversion { 
 
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_INSENSITIVITY = 64, 
    ALLOW_CASE_INSENSIBILITY = 64,  // Deprecated 
    ALLOW_HEX_FLOATS = 128, 
  }; 
 
  static const uc16 kNoSeparator = '\0'; 
 
  // 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_INSENSITIVITY: ignore case of characters for special values: 
  //      infinity and nan. 
  //  - ALLOW_HEX_FLOATS: allows hexadecimal float literals. 
  //      This *must* start with "0x" and separate the exponent with "p". 
  //      Examples: 0x1.2p3 == 9.0 
  //                0x10.1p0 == 16.0625 
  //      ALLOW_HEX and ALLOW_HEX_FLOATS are indendent. 
  // 
  // 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. 
  // 
  // If the separator character is not kNoSeparator, then that specific 
  // character is ignored when in between two valid digits of the significant. 
  // It is not allowed to appear in the exponent. 
  // It is not allowed to lead or trail the number. 
  // It is not allowed to appear twice next to each other. 
  // 
  // 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. 
  // 
  //  flags = NO_FLAGS, 
  //  separator = ' ': 
  //    StringToDouble("1 2 3 4") -> 1234.0 
  //    StringToDouble("1  2") -> NaN // junk_string_value 
  //    StringToDouble("1 000 000.0") -> 1000000.0 
  //    StringToDouble("1.000 000") -> 1.0 
  //    StringToDouble("1.0e1 000") -> NaN // junk_string_value 
  StringToDoubleConverter(int flags, 
                          double empty_string_value, 
                          double junk_string_value, 
                          const char* infinity_symbol, 
                          const char* nan_symbol, 
                          uc16 separator = kNoSeparator) 
      : flags_(flags), 
        empty_string_value_(empty_string_value), 
        junk_string_value_(junk_string_value), 
        infinity_symbol_(infinity_symbol), 
        nan_symbol_(nan_symbol), 
        separator_(separator) { 
  } 
 
  // 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_; 
  const uc16 separator_; 
 
  template <class Iterator> 
  double StringToIeee(Iterator start_pointer, 
                      int length, 
                      bool read_as_double, 
                      int* processed_characters_count) const; 
 
  DOUBLE_CONVERSION_DISALLOW_IMPLICIT_CONSTRUCTORS(StringToDoubleConverter); 
}; 
 
}  // namespace double_conversion 
 
// ICU PATCH: Close ICU namespace 
U_NAMESPACE_END 
 
#endif  // DOUBLE_CONVERSION_STRING_TO_DOUBLE_H_ 
#endif // ICU PATCH: close #if !UCONFIG_NO_FORMATTING