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double-conversion.h
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27 
28 #ifndef DOUBLE_CONVERSION_DOUBLE_CONVERSION_H_
29 #define DOUBLE_CONVERSION_DOUBLE_CONVERSION_H_
30 
31 #include "utils.h"
32 
33 #include "pxr/pxr.h"
34 
35 PXR_NAMESPACE_OPEN_SCOPE
36 
37 namespace pxr_double_conversion {
38 
39 class DoubleToStringConverter {
40  public:
41  // When calling ToFixed with a double > 10^kMaxFixedDigitsBeforePoint
42  // or a requested_digits parameter > kMaxFixedDigitsAfterPoint then the
43  // function returns false.
44  static const int kMaxFixedDigitsBeforePoint = 60;
45  static const int kMaxFixedDigitsAfterPoint = 60;
46 
47  // When calling ToExponential with a requested_digits
48  // parameter > kMaxExponentialDigits then the function returns false.
49  static const int kMaxExponentialDigits = 120;
50 
51  // When calling ToPrecision with a requested_digits
52  // parameter < kMinPrecisionDigits or requested_digits > kMaxPrecisionDigits
53  // then the function returns false.
54  static const int kMinPrecisionDigits = 1;
55  static const int kMaxPrecisionDigits = 120;
56 
57  enum Flags {
58  NO_FLAGS = 0,
59  EMIT_POSITIVE_EXPONENT_SIGN = 1,
60  EMIT_TRAILING_DECIMAL_POINT = 2,
61  EMIT_TRAILING_ZERO_AFTER_POINT = 4,
62  UNIQUE_ZERO = 8
63  };
64 
65  // Flags should be a bit-or combination of the possible Flags-enum.
66  // - NO_FLAGS: no special flags.
67  // - EMIT_POSITIVE_EXPONENT_SIGN: when the number is converted into exponent
68  // form, emits a '+' for positive exponents. Example: 1.2e+2.
69  // - EMIT_TRAILING_DECIMAL_POINT: when the input number is an integer and is
70  // converted into decimal format then a trailing decimal point is appended.
71  // Example: 2345.0 is converted to "2345.".
72  // - EMIT_TRAILING_ZERO_AFTER_POINT: in addition to a trailing decimal point
73  // emits a trailing '0'-character. This flag requires the
74  // EXMIT_TRAILING_DECIMAL_POINT flag.
75  // Example: 2345.0 is converted to "2345.0".
76  // - UNIQUE_ZERO: "-0.0" is converted to "0.0".
77  //
78  // Infinity symbol and nan_symbol provide the string representation for these
79  // special values. If the string is NULL and the special value is encountered
80  // then the conversion functions return false.
81  //
82  // The exponent_character is used in exponential representations. It is
83  // usually 'e' or 'E'.
84  //
85  // When converting to the shortest representation the converter will
86  // represent input numbers in decimal format if they are in the interval
87  // [10^decimal_in_shortest_low; 10^decimal_in_shortest_high[
88  // (lower boundary included, greater boundary excluded).
89  // Example: with decimal_in_shortest_low = -6 and
90  // decimal_in_shortest_high = 21:
91  // ToShortest(0.000001) -> "0.000001"
92  // ToShortest(0.0000001) -> "1e-7"
93  // ToShortest(111111111111111111111.0) -> "111111111111111110000"
94  // ToShortest(100000000000000000000.0) -> "100000000000000000000"
95  // ToShortest(1111111111111111111111.0) -> "1.1111111111111111e+21"
96  //
97  // When converting to precision mode the converter may add
98  // max_leading_padding_zeroes before returning the number in exponential
99  // format.
100  // Example with max_leading_padding_zeroes_in_precision_mode = 6.
101  // ToPrecision(0.0000012345, 2) -> "0.0000012"
102  // ToPrecision(0.00000012345, 2) -> "1.2e-7"
103  // Similarily the converter may add up to
104  // max_trailing_padding_zeroes_in_precision_mode in precision mode to avoid
105  // returning an exponential representation. A zero added by the
106  // EMIT_TRAILING_ZERO_AFTER_POINT flag is counted for this limit.
107  // Examples for max_trailing_padding_zeroes_in_precision_mode = 1:
108  // ToPrecision(230.0, 2) -> "230"
109  // ToPrecision(230.0, 2) -> "230." with EMIT_TRAILING_DECIMAL_POINT.
110  // ToPrecision(230.0, 2) -> "2.3e2" with EMIT_TRAILING_ZERO_AFTER_POINT.
111  DoubleToStringConverter(int flags,
112  const char* infinity_symbol,
113  const char* nan_symbol,
114  char exponent_character,
115  int decimal_in_shortest_low,
116  int decimal_in_shortest_high,
117  int max_leading_padding_zeroes_in_precision_mode,
118  int max_trailing_padding_zeroes_in_precision_mode)
119  : flags_(flags),
120  infinity_symbol_(infinity_symbol),
121  nan_symbol_(nan_symbol),
122  exponent_character_(exponent_character),
123  decimal_in_shortest_low_(decimal_in_shortest_low),
124  decimal_in_shortest_high_(decimal_in_shortest_high),
125  max_leading_padding_zeroes_in_precision_mode_(
126  max_leading_padding_zeroes_in_precision_mode),
127  max_trailing_padding_zeroes_in_precision_mode_(
128  max_trailing_padding_zeroes_in_precision_mode) {
129  // When 'trailing zero after the point' is set, then 'trailing point'
130  // must be set too.
131  ASSERT(((flags & EMIT_TRAILING_DECIMAL_POINT) != 0) ||
132  !((flags & EMIT_TRAILING_ZERO_AFTER_POINT) != 0));
133  }
134 
135  // Returns a converter following the EcmaScript specification.
136  static const DoubleToStringConverter& EcmaScriptConverter();
137 
138  // Computes the shortest string of digits that correctly represent the input
139  // number. Depending on decimal_in_shortest_low and decimal_in_shortest_high
140  // (see constructor) it then either returns a decimal representation, or an
141  // exponential representation.
142  // Example with decimal_in_shortest_low = -6,
143  // decimal_in_shortest_high = 21,
144  // EMIT_POSITIVE_EXPONENT_SIGN activated, and
145  // EMIT_TRAILING_DECIMAL_POINT deactived:
146  // ToShortest(0.000001) -> "0.000001"
147  // ToShortest(0.0000001) -> "1e-7"
148  // ToShortest(111111111111111111111.0) -> "111111111111111110000"
149  // ToShortest(100000000000000000000.0) -> "100000000000000000000"
150  // ToShortest(1111111111111111111111.0) -> "1.1111111111111111e+21"
151  //
152  // Note: the conversion may round the output if the returned string
153  // is accurate enough to uniquely identify the input-number.
154  // For example the most precise representation of the double 9e59 equals
155  // "899999999999999918767229449717619953810131273674690656206848", but
156  // the converter will return the shorter (but still correct) "9e59".
157  //
158  // Returns true if the conversion succeeds. The conversion always succeeds
159  // except when the input value is special and no infinity_symbol or
160  // nan_symbol has been given to the constructor.
161  bool ToShortest(double value, StringBuilder* result_builder) const {
162  return ToShortestIeeeNumber(value, result_builder, SHORTEST);
163  }
164 
165  // Same as ToShortest, but for single-precision floats.
166  bool ToShortestSingle(float value, StringBuilder* result_builder) const {
167  return ToShortestIeeeNumber(value, result_builder, SHORTEST_SINGLE);
168  }
169 
170 
171  // Computes a decimal representation with a fixed number of digits after the
172  // decimal point. The last emitted digit is rounded.
173  //
174  // Examples:
175  // ToFixed(3.12, 1) -> "3.1"
176  // ToFixed(3.1415, 3) -> "3.142"
177  // ToFixed(1234.56789, 4) -> "1234.5679"
178  // ToFixed(1.23, 5) -> "1.23000"
179  // ToFixed(0.1, 4) -> "0.1000"
180  // ToFixed(1e30, 2) -> "1000000000000000019884624838656.00"
181  // ToFixed(0.1, 30) -> "0.100000000000000005551115123126"
182  // ToFixed(0.1, 17) -> "0.10000000000000001"
183  //
184  // If requested_digits equals 0, then the tail of the result depends on
185  // the EMIT_TRAILING_DECIMAL_POINT and EMIT_TRAILING_ZERO_AFTER_POINT.
186  // Examples, for requested_digits == 0,
187  // let EMIT_TRAILING_DECIMAL_POINT and EMIT_TRAILING_ZERO_AFTER_POINT be
188  // - false and false: then 123.45 -> 123
189  // 0.678 -> 1
190  // - true and false: then 123.45 -> 123.
191  // 0.678 -> 1.
192  // - true and true: then 123.45 -> 123.0
193  // 0.678 -> 1.0
194  //
195  // Returns true if the conversion succeeds. The conversion always succeeds
196  // except for the following cases:
197  // - the input value is special and no infinity_symbol or nan_symbol has
198  // been provided to the constructor,
199  // - 'value' > 10^kMaxFixedDigitsBeforePoint, or
200  // - 'requested_digits' > kMaxFixedDigitsAfterPoint.
201  // The last two conditions imply that the result will never contain more than
202  // 1 + kMaxFixedDigitsBeforePoint + 1 + kMaxFixedDigitsAfterPoint characters
203  // (one additional character for the sign, and one for the decimal point).
204  bool ToFixed(double value,
205  int requested_digits,
206  StringBuilder* result_builder) const;
207 
208  // Computes a representation in exponential format with requested_digits
209  // after the decimal point. The last emitted digit is rounded.
210  // If requested_digits equals -1, then the shortest exponential representation
211  // is computed.
212  //
213  // Examples with EMIT_POSITIVE_EXPONENT_SIGN deactivated, and
214  // exponent_character set to 'e'.
215  // ToExponential(3.12, 1) -> "3.1e0"
216  // ToExponential(5.0, 3) -> "5.000e0"
217  // ToExponential(0.001, 2) -> "1.00e-3"
218  // ToExponential(3.1415, -1) -> "3.1415e0"
219  // ToExponential(3.1415, 4) -> "3.1415e0"
220  // ToExponential(3.1415, 3) -> "3.142e0"
221  // ToExponential(123456789000000, 3) -> "1.235e14"
222  // ToExponential(1000000000000000019884624838656.0, -1) -> "1e30"
223  // ToExponential(1000000000000000019884624838656.0, 32) ->
224  // "1.00000000000000001988462483865600e30"
225  // ToExponential(1234, 0) -> "1e3"
226  //
227  // Returns true if the conversion succeeds. The conversion always succeeds
228  // except for the following cases:
229  // - the input value is special and no infinity_symbol or nan_symbol has
230  // been provided to the constructor,
231  // - 'requested_digits' > kMaxExponentialDigits.
232  // The last condition implies that the result will never contain more than
233  // kMaxExponentialDigits + 8 characters (the sign, the digit before the
234  // decimal point, the decimal point, the exponent character, the
235  // exponent's sign, and at most 3 exponent digits).
236  bool ToExponential(double value,
237  int requested_digits,
238  StringBuilder* result_builder) const;
239 
240  // Computes 'precision' leading digits of the given 'value' and returns them
241  // either in exponential or decimal format, depending on
242  // max_{leading|trailing}_padding_zeroes_in_precision_mode (given to the
243  // constructor).
244  // The last computed digit is rounded.
245  //
246  // Example with max_leading_padding_zeroes_in_precision_mode = 6.
247  // ToPrecision(0.0000012345, 2) -> "0.0000012"
248  // ToPrecision(0.00000012345, 2) -> "1.2e-7"
249  // Similarily the converter may add up to
250  // max_trailing_padding_zeroes_in_precision_mode in precision mode to avoid
251  // returning an exponential representation. A zero added by the
252  // EMIT_TRAILING_ZERO_AFTER_POINT flag is counted for this limit.
253  // Examples for max_trailing_padding_zeroes_in_precision_mode = 1:
254  // ToPrecision(230.0, 2) -> "230"
255  // ToPrecision(230.0, 2) -> "230." with EMIT_TRAILING_DECIMAL_POINT.
256  // ToPrecision(230.0, 2) -> "2.3e2" with EMIT_TRAILING_ZERO_AFTER_POINT.
257  // Examples for max_trailing_padding_zeroes_in_precision_mode = 3, and no
258  // EMIT_TRAILING_ZERO_AFTER_POINT:
259  // ToPrecision(123450.0, 6) -> "123450"
260  // ToPrecision(123450.0, 5) -> "123450"
261  // ToPrecision(123450.0, 4) -> "123500"
262  // ToPrecision(123450.0, 3) -> "123000"
263  // ToPrecision(123450.0, 2) -> "1.2e5"
264  //
265  // Returns true if the conversion succeeds. The conversion always succeeds
266  // except for the following cases:
267  // - the input value is special and no infinity_symbol or nan_symbol has
268  // been provided to the constructor,
269  // - precision < kMinPericisionDigits
270  // - precision > kMaxPrecisionDigits
271  // The last condition implies that the result will never contain more than
272  // kMaxPrecisionDigits + 7 characters (the sign, the decimal point, the
273  // exponent character, the exponent's sign, and at most 3 exponent digits).
274  bool ToPrecision(double value,
275  int precision,
276  StringBuilder* result_builder) const;
277 
278  enum DtoaMode {
279  // Produce the shortest correct representation.
280  // For example the output of 0.299999999999999988897 is (the less accurate
281  // but correct) 0.3.
282  SHORTEST,
283  // Same as SHORTEST, but for single-precision floats.
284  SHORTEST_SINGLE,
285  // Produce a fixed number of digits after the decimal point.
286  // For instance fixed(0.1, 4) becomes 0.1000
287  // If the input number is big, the output will be big.
288  FIXED,
289  // Fixed number of digits (independent of the decimal point).
290  PRECISION
291  };
292 
293  // The maximal number of digits that are needed to emit a double in base 10.
294  // A higher precision can be achieved by using more digits, but the shortest
295  // accurate representation of any double will never use more digits than
296  // kBase10MaximalLength.
297  // Note that DoubleToAscii null-terminates its input. So the given buffer
298  // should be at least kBase10MaximalLength + 1 characters long.
299  static const int kBase10MaximalLength = 17;
300 
301  // Converts the given double 'v' to ascii. 'v' must not be NaN, +Infinity, or
302  // -Infinity. In SHORTEST_SINGLE-mode this restriction also applies to 'v'
303  // after it has been casted to a single-precision float. That is, in this
304  // mode static_cast<float>(v) must not be NaN, +Infinity or -Infinity.
305  //
306  // The result should be interpreted as buffer * 10^(point-length).
307  //
308  // The output depends on the given mode:
309  // - SHORTEST: produce the least amount of digits for which the internal
310  // identity requirement is still satisfied. If the digits are printed
311  // (together with the correct exponent) then reading this number will give
312  // 'v' again. The buffer will choose the representation that is closest to
313  // 'v'. If there are two at the same distance, than the one farther away
314  // from 0 is chosen (halfway cases - ending with 5 - are rounded up).
315  // In this mode the 'requested_digits' parameter is ignored.
316  // - SHORTEST_SINGLE: same as SHORTEST but with single-precision.
317  // - FIXED: produces digits necessary to print a given number with
318  // 'requested_digits' digits after the decimal point. The produced digits
319  // might be too short in which case the caller has to fill the remainder
320  // with '0's.
321  // Example: toFixed(0.001, 5) is allowed to return buffer="1", point=-2.
322  // Halfway cases are rounded towards +/-Infinity (away from 0). The call
323  // toFixed(0.15, 2) thus returns buffer="2", point=0.
324  // The returned buffer may contain digits that would be truncated from the
325  // shortest representation of the input.
326  // - PRECISION: produces 'requested_digits' where the first digit is not '0'.
327  // Even though the length of produced digits usually equals
328  // 'requested_digits', the function is allowed to return fewer digits, in
329  // which case the caller has to fill the missing digits with '0's.
330  // Halfway cases are again rounded away from 0.
331  // DoubleToAscii expects the given buffer to be big enough to hold all
332  // digits and a terminating null-character. In SHORTEST-mode it expects a
333  // buffer of at least kBase10MaximalLength + 1. In all other modes the
334  // requested_digits parameter and the padding-zeroes limit the size of the
335  // output. Don't forget the decimal point, the exponent character and the
336  // terminating null-character when computing the maximal output size.
337  // The given length is only used in debug mode to ensure the buffer is big
338  // enough.
339  static void DoubleToAscii(double v,
340  DtoaMode mode,
341  int requested_digits,
342  char* buffer,
343  int buffer_length,
344  bool* sign,
345  int* length,
346  int* point);
347 
348  private:
349  // Implementation for ToShortest and ToShortestSingle.
350  bool ToShortestIeeeNumber(double value,
351  StringBuilder* result_builder,
352  DtoaMode mode) const;
353 
354  // If the value is a special value (NaN or Infinity) constructs the
355  // corresponding string using the configured infinity/nan-symbol.
356  // If either of them is NULL or the value is not special then the
357  // function returns false.
358  bool HandleSpecialValues(double value, StringBuilder* result_builder) const;
359  // Constructs an exponential representation (i.e. 1.234e56).
360  // The given exponent assumes a decimal point after the first decimal digit.
361  void CreateExponentialRepresentation(const char* decimal_digits,
362  int length,
363  int exponent,
364  StringBuilder* result_builder) const;
365  // Creates a decimal representation (i.e 1234.5678).
366  void CreateDecimalRepresentation(const char* decimal_digits,
367  int length,
368  int decimal_point,
369  int digits_after_point,
370  StringBuilder* result_builder) const;
371 
372  const int flags_;
373  const char* const infinity_symbol_;
374  const char* const nan_symbol_;
375  const char exponent_character_;
376  const int decimal_in_shortest_low_;
377  const int decimal_in_shortest_high_;
378  const int max_leading_padding_zeroes_in_precision_mode_;
379  const int max_trailing_padding_zeroes_in_precision_mode_;
380 
381  DISALLOW_IMPLICIT_CONSTRUCTORS(DoubleToStringConverter);
382 };
383 
384 
385 class StringToDoubleConverter {
386  public:
387  // Enumeration for allowing octals and ignoring junk when converting
388  // strings to numbers.
389  enum Flags {
390  NO_FLAGS = 0,
391  ALLOW_HEX = 1,
392  ALLOW_OCTALS = 2,
393  ALLOW_TRAILING_JUNK = 4,
394  ALLOW_LEADING_SPACES = 8,
395  ALLOW_TRAILING_SPACES = 16,
396  ALLOW_SPACES_AFTER_SIGN = 32
397  };
398 
399  // Flags should be a bit-or combination of the possible Flags-enum.
400  // - NO_FLAGS: no special flags.
401  // - ALLOW_HEX: recognizes the prefix "0x". Hex numbers may only be integers.
402  // Ex: StringToDouble("0x1234") -> 4660.0
403  // In StringToDouble("0x1234.56") the characters ".56" are trailing
404  // junk. The result of the call is hence dependent on
405  // the ALLOW_TRAILING_JUNK flag and/or the junk value.
406  // With this flag "0x" is a junk-string. Even with ALLOW_TRAILING_JUNK,
407  // the string will not be parsed as "0" followed by junk.
408  //
409  // - ALLOW_OCTALS: recognizes the prefix "0" for octals:
410  // If a sequence of octal digits starts with '0', then the number is
411  // read as octal integer. Octal numbers may only be integers.
412  // Ex: StringToDouble("01234") -> 668.0
413  // StringToDouble("012349") -> 12349.0 // Not a sequence of octal
414  // // digits.
415  // In StringToDouble("01234.56") the characters ".56" are trailing
416  // junk. The result of the call is hence dependent on
417  // the ALLOW_TRAILING_JUNK flag and/or the junk value.
418  // In StringToDouble("01234e56") the characters "e56" are trailing
419  // junk, too.
420  // - ALLOW_TRAILING_JUNK: ignore trailing characters that are not part of
421  // a double literal.
422  // - ALLOW_LEADING_SPACES: skip over leading whitespace, including spaces,
423  // new-lines, and tabs.
424  // - ALLOW_TRAILING_SPACES: ignore trailing whitespace.
425  // - ALLOW_SPACES_AFTER_SIGN: ignore whitespace after the sign.
426  // Ex: StringToDouble("- 123.2") -> -123.2.
427  // StringToDouble("+ 123.2") -> 123.2
428  //
429  // empty_string_value is returned when an empty string is given as input.
430  // If ALLOW_LEADING_SPACES or ALLOW_TRAILING_SPACES are set, then a string
431  // containing only spaces is converted to the 'empty_string_value', too.
432  //
433  // junk_string_value is returned when
434  // a) ALLOW_TRAILING_JUNK is not set, and a junk character (a character not
435  // part of a double-literal) is found.
436  // b) ALLOW_TRAILING_JUNK is set, but the string does not start with a
437  // double literal.
438  //
439  // infinity_symbol and nan_symbol are strings that are used to detect
440  // inputs that represent infinity and NaN. They can be null, in which case
441  // they are ignored.
442  // The conversion routine first reads any possible signs. Then it compares the
443  // following character of the input-string with the first character of
444  // the infinity, and nan-symbol. If either matches, the function assumes, that
445  // a match has been found, and expects the following input characters to match
446  // the remaining characters of the special-value symbol.
447  // This means that the following restrictions apply to special-value symbols:
448  // - they must not start with signs ('+', or '-'),
449  // - they must not have the same first character.
450  // - they must not start with digits.
451  //
452  // Examples:
453  // flags = ALLOW_HEX | ALLOW_TRAILING_JUNK,
454  // empty_string_value = 0.0,
455  // junk_string_value = NaN,
456  // infinity_symbol = "infinity",
457  // nan_symbol = "nan":
458  // StringToDouble("0x1234") -> 4660.0.
459  // StringToDouble("0x1234K") -> 4660.0.
460  // StringToDouble("") -> 0.0 // empty_string_value.
461  // StringToDouble(" ") -> NaN // junk_string_value.
462  // StringToDouble(" 1") -> NaN // junk_string_value.
463  // StringToDouble("0x") -> NaN // junk_string_value.
464  // StringToDouble("-123.45") -> -123.45.
465  // StringToDouble("--123.45") -> NaN // junk_string_value.
466  // StringToDouble("123e45") -> 123e45.
467  // StringToDouble("123E45") -> 123e45.
468  // StringToDouble("123e+45") -> 123e45.
469  // StringToDouble("123E-45") -> 123e-45.
470  // StringToDouble("123e") -> 123.0 // trailing junk ignored.
471  // StringToDouble("123e-") -> 123.0 // trailing junk ignored.
472  // StringToDouble("+NaN") -> NaN // NaN string literal.
473  // StringToDouble("-infinity") -> -inf. // infinity literal.
474  // StringToDouble("Infinity") -> NaN // junk_string_value.
475  //
476  // flags = ALLOW_OCTAL | ALLOW_LEADING_SPACES,
477  // empty_string_value = 0.0,
478  // junk_string_value = NaN,
479  // infinity_symbol = NULL,
480  // nan_symbol = NULL:
481  // StringToDouble("0x1234") -> NaN // junk_string_value.
482  // StringToDouble("01234") -> 668.0.
483  // StringToDouble("") -> 0.0 // empty_string_value.
484  // StringToDouble(" ") -> 0.0 // empty_string_value.
485  // StringToDouble(" 1") -> 1.0
486  // StringToDouble("0x") -> NaN // junk_string_value.
487  // StringToDouble("0123e45") -> NaN // junk_string_value.
488  // StringToDouble("01239E45") -> 1239e45.
489  // StringToDouble("-infinity") -> NaN // junk_string_value.
490  // StringToDouble("NaN") -> NaN // junk_string_value.
491  StringToDoubleConverter(int flags,
492  double empty_string_value,
493  double junk_string_value,
494  const char* infinity_symbol,
495  const char* nan_symbol)
496  : flags_(flags),
497  empty_string_value_(empty_string_value),
498  junk_string_value_(junk_string_value),
499  infinity_symbol_(infinity_symbol),
500  nan_symbol_(nan_symbol) {
501  }
502 
503  // Performs the conversion.
504  // The output parameter 'processed_characters_count' is set to the number
505  // of characters that have been processed to read the number.
506  // Spaces than are processed with ALLOW_{LEADING|TRAILING}_SPACES are included
507  // in the 'processed_characters_count'. Trailing junk is never included.
508  double StringToDouble(const char* buffer,
509  int length,
510  int* processed_characters_count) const;
511 
512  // Same as StringToDouble above but for 16 bit characters.
513  double StringToDouble(const uc16* buffer,
514  int length,
515  int* processed_characters_count) const;
516 
517  // Same as StringToDouble but reads a float.
518  // Note that this is not equivalent to static_cast<float>(StringToDouble(...))
519  // due to potential double-rounding.
520  float StringToFloat(const char* buffer,
521  int length,
522  int* processed_characters_count) const;
523 
524  // Same as StringToFloat above but for 16 bit characters.
525  float StringToFloat(const uc16* buffer,
526  int length,
527  int* processed_characters_count) const;
528 
529  private:
530  const int flags_;
531  const double empty_string_value_;
532  const double junk_string_value_;
533  const char* const infinity_symbol_;
534  const char* const nan_symbol_;
535 
536  template <class Iterator>
537  double StringToIeee(Iterator start_pointer,
538  int length,
539  bool read_as_double,
540  int* processed_characters_count) const;
541 
542  DISALLOW_IMPLICIT_CONSTRUCTORS(StringToDoubleConverter);
543 };
544 
545 } // namespace pxr_double_conversion
546 
547 PXR_NAMESPACE_CLOSE_SCOPE
548 
549 #endif // DOUBLE_CONVERSION_DOUBLE_CONVERSION_H_