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  // v = buf * 10^(n-k)
  // k is the length of the buffer (number of decimal digits)
  // n is the position of the decimal point relative to the start of the buffer.

  if (k <= n && n <= max_exp) {
    // digits[000]
    // len <= max_exp + 2

    std::memset(buf + k, '0', static_cast<size_t>(n) - static_cast<size_t>(k));
    // Make it look like a floating-point number (#362, #378)
    buf[n + 0] = '.';
    buf[n + 1] = '0';
    return buf + (static_cast<size_t>(n)) + 2;
  }

  if (0 < n && n <= max_exp) {
    // dig.its
    // len <= max_digits10 + 1
    std::memmove(buf + (static_cast<size_t>(n) + 1), buf + n,
                 static_cast<size_t>(k) - static_cast<size_t>(n));
    buf[n] = '.';
    return buf + (static_cast<size_t>(k) + 1U);
  }

  if (min_exp < n && n <= 0) {
    // 0.[000]digits
    // len <= 2 + (-min_exp - 1) + max_digits10

    std::memmove(buf + (2 + static_cast<size_t>(-n)), buf,
                 static_cast<size_t>(k));
    buf[0] = '0';
    buf[1] = '.';
    std::memset(buf + 2, '0', static_cast<size_t>(-n));
    return buf + (2U + static_cast<size_t>(-n) + static_cast<size_t>(k));
  }

  if (k == 1) {
    // dE+123
    // len <= 1 + 5

    buf += 1;
  } else {
    // d.igitsE+123
    // len <= max_digits10 + 1 + 5

    std::memmove(buf + 2, buf + 1, static_cast<size_t>(k) - 1);
    buf[1] = '.';
    buf += 1 + static_cast<size_t>(k);
  }

  *buf++ = 'e';
  return append_exponent(buf, n - 1);
}

} // namespace dtoa_impl

/*!
The format of the resulting decimal representation is similar to printf's %g
format. Returns an iterator pointing past-the-end of the decimal representation.
@note The input number must be finite, i.e. NaN's and Inf's are not supported.
@note The buffer must be large enough.
@note The result is NOT null-terminated.
*/
char *to_chars(char *first, const char *last, double value) {
  static_cast<void>(last); // maybe unused - fix warning
  bool negative = std::signbit(value);
  if (negative) {
    value = -value;
    *first++ = '-';
  }

  if (value == 0) // +-0
  {
    *first++ = '0';
    // Make it look like a floating-point number (#362, #378)
    *first++ = '.';
    *first++ = '0';
    return first;
  }
  // Compute v = buffer * 10^decimal_exponent.
  // The decimal digits are stored in the buffer, which needs to be interpreted
  // as an unsigned decimal integer.
  // len is the length of the buffer, i.e. the number of decimal digits.
  int len = 0;
  int decimal_exponent = 0;
  dtoa_impl::grisu2(first, len, decimal_exponent, value);
  // Format the buffer like printf("%.*g", prec, value)
  constexpr int kMinExp = -4;
  constexpr int kMaxExp = std::numeric_limits<double>::digits10;

  return dtoa_impl::format_buffer(first, len, decimal_exponent, kMinExp,
                                  kMaxExp);
}
} // namespace internal
} // namespace simdjson

#endif // SIMDJSON_SRC_TO_CHARS_CPP
/* end file to_chars.cpp */
/* including from_chars.cpp: #include <from_chars.cpp> */
/* begin file from_chars.cpp */
#ifndef SIMDJSON_SRC_FROM_CHARS_CPP
#define SIMDJSON_SRC_FROM_CHARS_CPP

/* skipped duplicate #include <base.h> */

#include <cstdint>
#include <cstring>
#include <limits>

namespace simdjson {
namespace internal {

/**
 * The code in the internal::from_chars function is meant to handle the floating-point number parsing
 * when we have more than 19 digits in the decimal mantissa. This should only be seen
 * in adversarial scenarios: we do not expect production systems to even produce
 * such floating-point numbers.
 *
 * The parser is based on work by Nigel Tao (at https://github.com/google/wuffs/)
 * who credits Ken Thompson for the design (via a reference to the Go source