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28 #ifndef DOUBLE_CONVERSION_DOUBLE_CONVERSION_H_
29 #define DOUBLE_CONVERSION_DOUBLE_CONVERSION_H_
33 namespace double_conversion
{
35 class DoubleToStringConverter
{
37 // When calling ToFixed with a double > 10^kMaxFixedDigitsBeforePoint
38 // or a requested_digits parameter > kMaxFixedDigitsAfterPoint then the
39 // function returns false.
40 static const int kMaxFixedDigitsBeforePoint
= 60;
41 static const int kMaxFixedDigitsAfterPoint
= 60;
43 // When calling ToExponential with a requested_digits
44 // parameter > kMaxExponentialDigits then the function returns false.
45 static const int kMaxExponentialDigits
= 120;
47 // When calling ToPrecision with a requested_digits
48 // parameter < kMinPrecisionDigits or requested_digits > kMaxPrecisionDigits
49 // then the function returns false.
50 static const int kMinPrecisionDigits
= 1;
51 static const int kMaxPrecisionDigits
= 120;
55 EMIT_POSITIVE_EXPONENT_SIGN
= 1,
56 EMIT_TRAILING_DECIMAL_POINT
= 2,
57 EMIT_TRAILING_ZERO_AFTER_POINT
= 4,
61 // Flags should be a bit-or combination of the possible Flags-enum.
62 // - NO_FLAGS: no special flags.
63 // - EMIT_POSITIVE_EXPONENT_SIGN: when the number is converted into exponent
64 // form, emits a '+' for positive exponents. Example: 1.2e+2.
65 // - EMIT_TRAILING_DECIMAL_POINT: when the input number is an integer and is
66 // converted into decimal format then a trailing decimal point is appended.
67 // Example: 2345.0 is converted to "2345.".
68 // - EMIT_TRAILING_ZERO_AFTER_POINT: in addition to a trailing decimal point
69 // emits a trailing '0'-character. This flag requires the
70 // EXMIT_TRAILING_DECIMAL_POINT flag.
71 // Example: 2345.0 is converted to "2345.0".
72 // - UNIQUE_ZERO: "-0.0" is converted to "0.0".
74 // Infinity symbol and nan_symbol provide the string representation for these
75 // special values. If the string is NULL and the special value is encountered
76 // then the conversion functions return false.
78 // The exponent_character is used in exponential representations. It is
79 // usually 'e' or 'E'.
81 // When converting to the shortest representation the converter will
82 // represent input numbers in decimal format if they are in the interval
83 // [10^decimal_in_shortest_low; 10^decimal_in_shortest_high[
84 // (lower boundary included, greater boundary excluded).
85 // Example: with decimal_in_shortest_low = -6 and
86 // decimal_in_shortest_high = 21:
87 // ToShortest(0.000001) -> "0.000001"
88 // ToShortest(0.0000001) -> "1e-7"
89 // ToShortest(111111111111111111111.0) -> "111111111111111110000"
90 // ToShortest(100000000000000000000.0) -> "100000000000000000000"
91 // ToShortest(1111111111111111111111.0) -> "1.1111111111111111e+21"
93 // When converting to precision mode the converter may add
94 // max_leading_padding_zeroes before returning the number in exponential
96 // Example with max_leading_padding_zeroes_in_precision_mode = 6.
97 // ToPrecision(0.0000012345, 2) -> "0.0000012"
98 // ToPrecision(0.00000012345, 2) -> "1.2e-7"
99 // Similarily the converter may add up to
100 // max_trailing_padding_zeroes_in_precision_mode in precision mode to avoid
101 // returning an exponential representation. A zero added by the
102 // EMIT_TRAILING_ZERO_AFTER_POINT flag is counted for this limit.
103 // Examples for max_trailing_padding_zeroes_in_precision_mode = 1:
104 // ToPrecision(230.0, 2) -> "230"
105 // ToPrecision(230.0, 2) -> "230." with EMIT_TRAILING_DECIMAL_POINT.
106 // ToPrecision(230.0, 2) -> "2.3e2" with EMIT_TRAILING_ZERO_AFTER_POINT.
108 // When converting numbers to scientific notation representation, if the mantissa of
109 // the representation is an integer number, the EMIT_TRAILING_DECIMAL_POINT flag will
110 // add a '.' character at the end of the representation:
111 // - With EMIT_TRAILING_DECIMAL_POINT enabled -> 0.0009 => 9.E-4
112 // - With EMIT_TRAILING_DECIMAL_POINT disabled -> 0.0009 => 9E-4
114 // If the mantissa is an integer and the EMIT_TRAILING_ZERO_AFTER_POINT flag is enabled
115 // it will add a '0' character at the end of the mantissa representation. Note that that
116 // flag depends on EMIT_TRAILING_DECIMAL_POINT flag be enabled.
117 // - With EMIT_TRAILING_ZERO_AFTER_POINT enabled -> 0.0009 => 9.0E-4
118 DoubleToStringConverter(int flags
,
119 const char* infinity_symbol
,
120 const char* nan_symbol
,
121 char exponent_character
,
122 int decimal_in_shortest_low
,
123 int decimal_in_shortest_high
,
124 int max_leading_padding_zeroes_in_precision_mode
,
125 int max_trailing_padding_zeroes_in_precision_mode
)
127 infinity_symbol_(infinity_symbol
),
128 nan_symbol_(nan_symbol
),
129 exponent_character_(exponent_character
),
130 decimal_in_shortest_low_(decimal_in_shortest_low
),
131 decimal_in_shortest_high_(decimal_in_shortest_high
),
132 max_leading_padding_zeroes_in_precision_mode_(
133 max_leading_padding_zeroes_in_precision_mode
),
134 max_trailing_padding_zeroes_in_precision_mode_(
135 max_trailing_padding_zeroes_in_precision_mode
) {
136 // When 'trailing zero after the point' is set, then 'trailing point'
138 ASSERT(((flags
& EMIT_TRAILING_DECIMAL_POINT
) != 0) ||
139 !((flags
& EMIT_TRAILING_ZERO_AFTER_POINT
) != 0));
142 // Returns a converter following the EcmaScript specification.
143 static const DoubleToStringConverter
& EcmaScriptConverter();
145 // Computes the shortest string of digits that correctly represent the input
146 // number. Depending on decimal_in_shortest_low and decimal_in_shortest_high
147 // (see constructor) it then either returns a decimal representation, or an
148 // exponential representation.
149 // Example with decimal_in_shortest_low = -6,
150 // decimal_in_shortest_high = 21,
151 // EMIT_POSITIVE_EXPONENT_SIGN activated, and
152 // EMIT_TRAILING_DECIMAL_POINT deactived:
153 // ToShortest(0.000001) -> "0.000001"
154 // ToShortest(0.0000001) -> "1e-7"
155 // ToShortest(111111111111111111111.0) -> "111111111111111110000"
156 // ToShortest(100000000000000000000.0) -> "100000000000000000000"
157 // ToShortest(1111111111111111111111.0) -> "1.1111111111111111e+21"
159 // Note: the conversion may round the output if the returned string
160 // is accurate enough to uniquely identify the input-number.
161 // For example the most precise representation of the double 9e59 equals
162 // "899999999999999918767229449717619953810131273674690656206848", but
163 // the converter will return the shorter (but still correct) "9e59".
165 // Returns true if the conversion succeeds. The conversion always succeeds
166 // except when the input value is special and no infinity_symbol or
167 // nan_symbol has been given to the constructor.
168 bool ToShortest(double value
, StringBuilder
* result_builder
) const {
169 return ToShortestIeeeNumber(value
, result_builder
, SHORTEST
);
172 // Same as ToShortest, but for single-precision floats.
173 bool ToShortestSingle(float value
, StringBuilder
* result_builder
) const {
174 return ToShortestIeeeNumber(value
, result_builder
, SHORTEST_SINGLE
);
178 // Computes a decimal representation with a fixed number of digits after the
179 // decimal point. The last emitted digit is rounded.
182 // ToFixed(3.12, 1) -> "3.1"
183 // ToFixed(3.1415, 3) -> "3.142"
184 // ToFixed(1234.56789, 4) -> "1234.5679"
185 // ToFixed(1.23, 5) -> "1.23000"
186 // ToFixed(0.1, 4) -> "0.1000"
187 // ToFixed(1e30, 2) -> "1000000000000000019884624838656.00"
188 // ToFixed(0.1, 30) -> "0.100000000000000005551115123126"
189 // ToFixed(0.1, 17) -> "0.10000000000000001"
191 // If requested_digits equals 0, then the tail of the result depends on
192 // the EMIT_TRAILING_DECIMAL_POINT and EMIT_TRAILING_ZERO_AFTER_POINT.
193 // Examples, for requested_digits == 0,
194 // let EMIT_TRAILING_DECIMAL_POINT and EMIT_TRAILING_ZERO_AFTER_POINT be
195 // - false and false: then 123.45 -> 123
197 // - true and false: then 123.45 -> 123.
199 // - true and true: then 123.45 -> 123.0
202 // Returns true if the conversion succeeds. The conversion always succeeds
203 // except for the following cases:
204 // - the input value is special and no infinity_symbol or nan_symbol has
205 // been provided to the constructor,
206 // - 'value' > 10^kMaxFixedDigitsBeforePoint, or
207 // - 'requested_digits' > kMaxFixedDigitsAfterPoint.
208 // The last two conditions imply that the result will never contain more than
209 // 1 + kMaxFixedDigitsBeforePoint + 1 + kMaxFixedDigitsAfterPoint characters
210 // (one additional character for the sign, and one for the decimal point).
211 bool ToFixed(double value
,
212 int requested_digits
,
213 StringBuilder
* result_builder
) const;
215 // Computes a representation in exponential format with requested_digits
216 // after the decimal point. The last emitted digit is rounded.
217 // If requested_digits equals -1, then the shortest exponential representation
220 // Examples with EMIT_POSITIVE_EXPONENT_SIGN deactivated, and
221 // exponent_character set to 'e'.
222 // ToExponential(3.12, 1) -> "3.1e0"
223 // ToExponential(5.0, 3) -> "5.000e0"
224 // ToExponential(0.001, 2) -> "1.00e-3"
225 // ToExponential(3.1415, -1) -> "3.1415e0"
226 // ToExponential(3.1415, 4) -> "3.1415e0"
227 // ToExponential(3.1415, 3) -> "3.142e0"
228 // ToExponential(123456789000000, 3) -> "1.235e14"
229 // ToExponential(1000000000000000019884624838656.0, -1) -> "1e30"
230 // ToExponential(1000000000000000019884624838656.0, 32) ->
231 // "1.00000000000000001988462483865600e30"
232 // ToExponential(1234, 0) -> "1e3"
234 // Returns true if the conversion succeeds. The conversion always succeeds
235 // except for the following cases:
236 // - the input value is special and no infinity_symbol or nan_symbol has
237 // been provided to the constructor,
238 // - 'requested_digits' > kMaxExponentialDigits.
239 // The last condition implies that the result will never contain more than
240 // kMaxExponentialDigits + 8 characters (the sign, the digit before the
241 // decimal point, the decimal point, the exponent character, the
242 // exponent's sign, and at most 3 exponent digits).
243 bool ToExponential(double value
,
244 int requested_digits
,
245 StringBuilder
* result_builder
) const;
247 // Computes 'precision' leading digits of the given 'value' and returns them
248 // either in exponential or decimal format, depending on
249 // max_{leading|trailing}_padding_zeroes_in_precision_mode (given to the
251 // The last computed digit is rounded.
253 // Example with max_leading_padding_zeroes_in_precision_mode = 6.
254 // ToPrecision(0.0000012345, 2) -> "0.0000012"
255 // ToPrecision(0.00000012345, 2) -> "1.2e-7"
256 // Similarily the converter may add up to
257 // max_trailing_padding_zeroes_in_precision_mode in precision mode to avoid
258 // returning an exponential representation. A zero added by the
259 // EMIT_TRAILING_ZERO_AFTER_POINT flag is counted for this limit.
260 // Examples for max_trailing_padding_zeroes_in_precision_mode = 1:
261 // ToPrecision(230.0, 2) -> "230"
262 // ToPrecision(230.0, 2) -> "230." with EMIT_TRAILING_DECIMAL_POINT.
263 // ToPrecision(230.0, 2) -> "2.3e2" with EMIT_TRAILING_ZERO_AFTER_POINT.
264 // Examples for max_trailing_padding_zeroes_in_precision_mode = 3, and no
265 // EMIT_TRAILING_ZERO_AFTER_POINT:
266 // ToPrecision(123450.0, 6) -> "123450"
267 // ToPrecision(123450.0, 5) -> "123450"
268 // ToPrecision(123450.0, 4) -> "123500"
269 // ToPrecision(123450.0, 3) -> "123000"
270 // ToPrecision(123450.0, 2) -> "1.2e5"
272 // Returns true if the conversion succeeds. The conversion always succeeds
273 // except for the following cases:
274 // - the input value is special and no infinity_symbol or nan_symbol has
275 // been provided to the constructor,
276 // - precision < kMinPericisionDigits
277 // - precision > kMaxPrecisionDigits
278 // The last condition implies that the result will never contain more than
279 // kMaxPrecisionDigits + 7 characters (the sign, the decimal point, the
280 // exponent character, the exponent's sign, and at most 3 exponent digits).
281 bool ToPrecision(double value
,
283 StringBuilder
* result_builder
) const;
286 // Produce the shortest correct representation.
287 // For example the output of 0.299999999999999988897 is (the less accurate
290 // Same as SHORTEST, but for single-precision floats.
292 // Produce a fixed number of digits after the decimal point.
293 // For instance fixed(0.1, 4) becomes 0.1000
294 // If the input number is big, the output will be big.
296 // Fixed number of digits (independent of the decimal point).
300 // The maximal number of digits that are needed to emit a double in base 10.
301 // A higher precision can be achieved by using more digits, but the shortest
302 // accurate representation of any double will never use more digits than
303 // kBase10MaximalLength.
304 // Note that DoubleToAscii null-terminates its input. So the given buffer
305 // should be at least kBase10MaximalLength + 1 characters long.
306 static const int kBase10MaximalLength
= 17;
308 // Converts the given double 'v' to digit characters. 'v' must not be NaN,
309 // +Infinity, or -Infinity. In SHORTEST_SINGLE-mode this restriction also
310 // applies to 'v' after it has been casted to a single-precision float. That
311 // is, in this mode static_cast<float>(v) must not be NaN, +Infinity or
314 // The result should be interpreted as buffer * 10^(point-length).
316 // The digits are written to the buffer in the platform's charset, which is
317 // often UTF-8 (with ASCII-range digits) but may be another charset, such
320 // The output depends on the given mode:
321 // - SHORTEST: produce the least amount of digits for which the internal
322 // identity requirement is still satisfied. If the digits are printed
323 // (together with the correct exponent) then reading this number will give
324 // 'v' again. The buffer will choose the representation that is closest to
325 // 'v'. If there are two at the same distance, than the one farther away
326 // from 0 is chosen (halfway cases - ending with 5 - are rounded up).
327 // In this mode the 'requested_digits' parameter is ignored.
328 // - SHORTEST_SINGLE: same as SHORTEST but with single-precision.
329 // - FIXED: produces digits necessary to print a given number with
330 // 'requested_digits' digits after the decimal point. The produced digits
331 // might be too short in which case the caller has to fill the remainder
333 // Example: toFixed(0.001, 5) is allowed to return buffer="1", point=-2.
334 // Halfway cases are rounded towards +/-Infinity (away from 0). The call
335 // toFixed(0.15, 2) thus returns buffer="2", point=0.
336 // The returned buffer may contain digits that would be truncated from the
337 // shortest representation of the input.
338 // - PRECISION: produces 'requested_digits' where the first digit is not '0'.
339 // Even though the length of produced digits usually equals
340 // 'requested_digits', the function is allowed to return fewer digits, in
341 // which case the caller has to fill the missing digits with '0's.
342 // Halfway cases are again rounded away from 0.
343 // DoubleToAscii expects the given buffer to be big enough to hold all
344 // digits and a terminating null-character. In SHORTEST-mode it expects a
345 // buffer of at least kBase10MaximalLength + 1. In all other modes the
346 // requested_digits parameter and the padding-zeroes limit the size of the
347 // output. Don't forget the decimal point, the exponent character and the
348 // terminating null-character when computing the maximal output size.
349 // The given length is only used in debug mode to ensure the buffer is big
351 static void DoubleToAscii(double v
,
353 int requested_digits
,
361 // Implementation for ToShortest and ToShortestSingle.
362 bool ToShortestIeeeNumber(double value
,
363 StringBuilder
* result_builder
,
364 DtoaMode mode
) const;
366 // If the value is a special value (NaN or Infinity) constructs the
367 // corresponding string using the configured infinity/nan-symbol.
368 // If either of them is NULL or the value is not special then the
369 // function returns false.
370 bool HandleSpecialValues(double value
, StringBuilder
* result_builder
) const;
371 // Constructs an exponential representation (i.e. 1.234e56).
372 // The given exponent assumes a decimal point after the first decimal digit.
373 void CreateExponentialRepresentation(const char* decimal_digits
,
376 StringBuilder
* result_builder
) const;
377 // Creates a decimal representation (i.e 1234.5678).
378 void CreateDecimalRepresentation(const char* decimal_digits
,
381 int digits_after_point
,
382 StringBuilder
* result_builder
) const;
385 const char* const infinity_symbol_
;
386 const char* const nan_symbol_
;
387 const char exponent_character_
;
388 const int decimal_in_shortest_low_
;
389 const int decimal_in_shortest_high_
;
390 const int max_leading_padding_zeroes_in_precision_mode_
;
391 const int max_trailing_padding_zeroes_in_precision_mode_
;
393 DC_DISALLOW_IMPLICIT_CONSTRUCTORS(DoubleToStringConverter
);
397 class StringToDoubleConverter
{
399 // Enumeration for allowing octals and ignoring junk when converting
400 // strings to numbers.
405 ALLOW_TRAILING_JUNK
= 4,
406 ALLOW_LEADING_SPACES
= 8,
407 ALLOW_TRAILING_SPACES
= 16,
408 ALLOW_SPACES_AFTER_SIGN
= 32,
409 ALLOW_CASE_INSENSIBILITY
= 64,
410 ALLOW_HEX_FLOATS
= 128,
413 static const uc16 kNoSeparator
= '\0';
415 // Flags should be a bit-or combination of the possible Flags-enum.
416 // - NO_FLAGS: no special flags.
417 // - ALLOW_HEX: recognizes the prefix "0x". Hex numbers may only be integers.
418 // Ex: StringToDouble("0x1234") -> 4660.0
419 // In StringToDouble("0x1234.56") the characters ".56" are trailing
420 // junk. The result of the call is hence dependent on
421 // the ALLOW_TRAILING_JUNK flag and/or the junk value.
422 // With this flag "0x" is a junk-string. Even with ALLOW_TRAILING_JUNK,
423 // the string will not be parsed as "0" followed by junk.
425 // - ALLOW_OCTALS: recognizes the prefix "0" for octals:
426 // If a sequence of octal digits starts with '0', then the number is
427 // read as octal integer. Octal numbers may only be integers.
428 // Ex: StringToDouble("01234") -> 668.0
429 // StringToDouble("012349") -> 12349.0 // Not a sequence of octal
431 // In StringToDouble("01234.56") the characters ".56" are trailing
432 // junk. The result of the call is hence dependent on
433 // the ALLOW_TRAILING_JUNK flag and/or the junk value.
434 // In StringToDouble("01234e56") the characters "e56" are trailing
436 // - ALLOW_TRAILING_JUNK: ignore trailing characters that are not part of
438 // - ALLOW_LEADING_SPACES: skip over leading whitespace, including spaces,
439 // new-lines, and tabs.
440 // - ALLOW_TRAILING_SPACES: ignore trailing whitespace.
441 // - ALLOW_SPACES_AFTER_SIGN: ignore whitespace after the sign.
442 // Ex: StringToDouble("- 123.2") -> -123.2.
443 // StringToDouble("+ 123.2") -> 123.2
444 // - ALLOW_CASE_INSENSIBILITY: ignore case of characters for special values:
446 // - ALLOW_HEX_FLOATS: allows hexadecimal float literals.
447 // This *must* start with "0x" and separate the exponent with "p".
448 // Examples: 0x1.2p3 == 9.0
449 // 0x10.1p0 == 16.0625
450 // ALLOW_HEX and ALLOW_HEX_FLOATS are indendent.
452 // empty_string_value is returned when an empty string is given as input.
453 // If ALLOW_LEADING_SPACES or ALLOW_TRAILING_SPACES are set, then a string
454 // containing only spaces is converted to the 'empty_string_value', too.
456 // junk_string_value is returned when
457 // a) ALLOW_TRAILING_JUNK is not set, and a junk character (a character not
458 // part of a double-literal) is found.
459 // b) ALLOW_TRAILING_JUNK is set, but the string does not start with a
462 // infinity_symbol and nan_symbol are strings that are used to detect
463 // inputs that represent infinity and NaN. They can be null, in which case
465 // The conversion routine first reads any possible signs. Then it compares the
466 // following character of the input-string with the first character of
467 // the infinity, and nan-symbol. If either matches, the function assumes, that
468 // a match has been found, and expects the following input characters to match
469 // the remaining characters of the special-value symbol.
470 // This means that the following restrictions apply to special-value symbols:
471 // - they must not start with signs ('+', or '-'),
472 // - they must not have the same first character.
473 // - they must not start with digits.
475 // If the separator character is not kNoSeparator, then that specific
476 // character is ignored when in between two valid digits of the significant.
477 // It is not allowed to appear in the exponent.
478 // It is not allowed to lead or trail the number.
479 // It is not allowed to appear twice next to each other.
482 // flags = ALLOW_HEX | ALLOW_TRAILING_JUNK,
483 // empty_string_value = 0.0,
484 // junk_string_value = NaN,
485 // infinity_symbol = "infinity",
486 // nan_symbol = "nan":
487 // StringToDouble("0x1234") -> 4660.0.
488 // StringToDouble("0x1234K") -> 4660.0.
489 // StringToDouble("") -> 0.0 // empty_string_value.
490 // StringToDouble(" ") -> NaN // junk_string_value.
491 // StringToDouble(" 1") -> NaN // junk_string_value.
492 // StringToDouble("0x") -> NaN // junk_string_value.
493 // StringToDouble("-123.45") -> -123.45.
494 // StringToDouble("--123.45") -> NaN // junk_string_value.
495 // StringToDouble("123e45") -> 123e45.
496 // StringToDouble("123E45") -> 123e45.
497 // StringToDouble("123e+45") -> 123e45.
498 // StringToDouble("123E-45") -> 123e-45.
499 // StringToDouble("123e") -> 123.0 // trailing junk ignored.
500 // StringToDouble("123e-") -> 123.0 // trailing junk ignored.
501 // StringToDouble("+NaN") -> NaN // NaN string literal.
502 // StringToDouble("-infinity") -> -inf. // infinity literal.
503 // StringToDouble("Infinity") -> NaN // junk_string_value.
505 // flags = ALLOW_OCTAL | ALLOW_LEADING_SPACES,
506 // empty_string_value = 0.0,
507 // junk_string_value = NaN,
508 // infinity_symbol = NULL,
509 // nan_symbol = NULL:
510 // StringToDouble("0x1234") -> NaN // junk_string_value.
511 // StringToDouble("01234") -> 668.0.
512 // StringToDouble("") -> 0.0 // empty_string_value.
513 // StringToDouble(" ") -> 0.0 // empty_string_value.
514 // StringToDouble(" 1") -> 1.0
515 // StringToDouble("0x") -> NaN // junk_string_value.
516 // StringToDouble("0123e45") -> NaN // junk_string_value.
517 // StringToDouble("01239E45") -> 1239e45.
518 // StringToDouble("-infinity") -> NaN // junk_string_value.
519 // StringToDouble("NaN") -> NaN // junk_string_value.
523 // StringToDouble("1 2 3 4") -> 1234.0
524 // StringToDouble("1 2") -> NaN // junk_string_value
525 // StringToDouble("1 000 000.0") -> 1000000.0
526 // StringToDouble("1.000 000") -> 1.0
527 // StringToDouble("1.0e1 000") -> NaN // junk_string_value
528 StringToDoubleConverter(int flags
,
529 double empty_string_value
,
530 double junk_string_value
,
531 const char* infinity_symbol
,
532 const char* nan_symbol
,
533 uc16 separator
= kNoSeparator
)
535 empty_string_value_(empty_string_value
),
536 junk_string_value_(junk_string_value
),
537 infinity_symbol_(infinity_symbol
),
538 nan_symbol_(nan_symbol
),
539 separator_(separator
) {
542 // Performs the conversion.
543 // The output parameter 'processed_characters_count' is set to the number
544 // of characters that have been processed to read the number.
545 // Spaces than are processed with ALLOW_{LEADING|TRAILING}_SPACES are included
546 // in the 'processed_characters_count'. Trailing junk is never included.
547 double StringToDouble(const char* buffer
,
549 int* processed_characters_count
) const;
551 // Same as StringToDouble above but for 16 bit characters.
552 double StringToDouble(const uc16
* buffer
,
554 int* processed_characters_count
) const;
556 // Same as StringToDouble but reads a float.
557 // Note that this is not equivalent to static_cast<float>(StringToDouble(...))
558 // due to potential double-rounding.
559 float StringToFloat(const char* buffer
,
561 int* processed_characters_count
) const;
563 // Same as StringToFloat above but for 16 bit characters.
564 float StringToFloat(const uc16
* buffer
,
566 int* processed_characters_count
) const;
570 const double empty_string_value_
;
571 const double junk_string_value_
;
572 const char* const infinity_symbol_
;
573 const char* const nan_symbol_
;
574 const uc16 separator_
;
576 template <class Iterator
>
577 double StringToIeee(Iterator start_pointer
,
580 int* processed_characters_count
) const;
582 DC_DISALLOW_IMPLICIT_CONSTRUCTORS(StringToDoubleConverter
);
585 } // namespace double_conversion
587 #endif // DOUBLE_CONVERSION_DOUBLE_CONVERSION_H_