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// Copyright 2010 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. 
 
#ifndef DOUBLE_CONVERSION_BIGNUM_DTOA_H_ 
#define DOUBLE_CONVERSION_BIGNUM_DTOA_H_ 
 
#include "utils.h" 
 
namespace double_conversion { 
 
enum BignumDtoaMode { 
  // Return the shortest correct representation. 
  // For example the output of 0.299999999999999988897 is (the less accurate but 
  // correct) 0.3. 
  BIGNUM_DTOA_SHORTEST, 
  // Same as BIGNUM_DTOA_SHORTEST but for single-precision floats. 
  BIGNUM_DTOA_SHORTEST_SINGLE, 
  // Return 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. 
  BIGNUM_DTOA_FIXED, 
  // Return a fixed number of digits, no matter what the exponent is. 
  BIGNUM_DTOA_PRECISION 
}; 
 
// Converts the given double 'v' to ascii. 
// The result should be interpreted as buffer * 10^(point-length). 
// The buffer will be null-terminated. 
// 
// The input v must be > 0 and different from NaN, and Infinity. 
// 
// 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 number is round up. 
//   In this mode the 'requested_digits' parameter is ignored. 
//  - 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 gaps with '0's. 
//   Example: toFixed(0.001, 5) is allowed to return buffer="1", point=-2. 
//   Halfway cases are rounded up. The call toFixed(0.15, 2) thus returns 
//     buffer="2", point=0. 
//   Note: the length of the returned buffer has no meaning wrt the significance 
//   of its digits. That is, just because it contains '0's does not mean that 
//   any other digit would not satisfy the internal identity requirement. 
//  - 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 up. 
// 'BignumDtoa' expects the given buffer to be big enough to hold all digits 
// and a terminating null-character. 
void BignumDtoa(double v, BignumDtoaMode mode, int requested_digits, 
                Vector<char> buffer, int* length, int* point); 
 
}  // namespace double_conversion 
 
#endif  // DOUBLE_CONVERSION_BIGNUM_DTOA_H_