typename std::enable_if<std::is_same<CharT,wchar_t>::value,double>::type
operator()(const CharT* s, size_t /*length*/) const
{
CharT *end = nullptr;
double val = wcstod(s, &end);
if (s == end)
{
JSONCONS_THROW(json_runtime_error<std::invalid_argument>("Convert string to double failed"));
}
return val;
}
typename std::enable_if<std::is_same<CharT,char>::value,double>::type
operator()(const CharT* s, size_t length) const
{
char *end = nullptr;
double val = strtold_l(s, &end, locale_);
if (s == end)
{
JSONCONS_THROW(json_runtime_error<std::invalid_argument>("Convert string to double failed"));
}
return val;
}
size_t operator()(double val, Result& result)
{
size_t count = 0;
chars_format format = override_.format() != chars_format() ? override_.format() : chars_format::general;
int decimal_places;
if (override_.decimal_places() != 0)
{
decimal_places = override_.decimal_places();
}
else
{
format = chars_format::general;
decimal_places = 0;
}
char number_buffer[200];
int length = 0;
switch (format)
{
case chars_format::fixed:
{
length = snprintf(number_buffer, sizeof(number_buffer), "%1.*f", decimal_places, val);
if (length < 0)
{
JSONCONS_THROW(json_runtime_error<std::invalid_argument>("print_double failed."));
}
dump_buffer(number_buffer, length, decimal_point_, result);
}
break;
case chars_format::scientific:
{
length = snprintf(number_buffer, sizeof(number_buffer), "%1.*e", decimal_places, val);
if (length < 0)
{
JSONCONS_THROW(json_runtime_error<std::invalid_argument>("print_double failed."));
}
dump_buffer(number_buffer, length, decimal_point_, result);
}
break;
case chars_format::general:
{
if (override_.precision() != 0)
{
int precision = override_.precision();
length = snprintf(number_buffer, sizeof(number_buffer), "%1.*g", precision, val);
if (length < 0)
{
JSONCONS_THROW(json_runtime_error<std::invalid_argument>("print_double failed."));
}
dump_buffer(number_buffer, length, decimal_point_, result);
}
else
{
if (!dtoa(val, decimal_point_, result))
{
JSONCONS_THROW(json_runtime_error<std::invalid_argument>("print_double failed."));
}
}
break;
}
default:
JSONCONS_THROW(json_runtime_error<std::invalid_argument>("print_double failed."));
break;
}
return count;
}
void operator()(double val, const floating_point_options& fmt, Writer& writer)
{
typedef typename Writer::char_type char_type;
chars_format format;
if (override_.format() != chars_format::hex)
{
format = override_.format();
}
else
{
format = fmt.format();
}
int precision;
int precision2 = 0;
if (override_.precision() != 0)
{
precision = override_.precision();
}
else if (fmt.precision() != 0)
{
precision = fmt.precision();
}
else
{
precision = std::numeric_limits<double>::digits10;
precision2 = std::numeric_limits<double>::max_digits10;
}
int decimal_places;
if (override_.decimal_places() != 0)
{
decimal_places = override_.decimal_places();
}
else if (fmt.decimal_places() != 0)
{
decimal_places = fmt.decimal_places();
}
else
{
format = chars_format::general;
}
char number_buffer[200];
int length = 0;
switch (format)
{
case chars_format::fixed:
{
length = snprintf(number_buffer, sizeof(number_buffer), "%1.*f", decimal_places, val);
if (length < 0)
{
JSONCONS_THROW(json_exception_impl<std::invalid_argument>("print_double failed."));
}
}
break;
case chars_format::scientific:
{
length = snprintf(number_buffer, sizeof(number_buffer), "%1.*e", decimal_places, val);
if (length < 0)
{
JSONCONS_THROW(json_exception_impl<std::invalid_argument>("print_double failed."));
}
}
break;
default:
{
length = snprintf(number_buffer, sizeof(number_buffer), "%1.*g", precision, val);
if (length < 0)
{
JSONCONS_THROW(json_exception_impl<std::invalid_argument>("print_double failed."));
}
if (precision2 > 0)
{
if (to_double_(number_buffer,sizeof(number_buffer)) != val)
{
length = snprintf(number_buffer, sizeof(number_buffer), "%1.*g", precision2, val);
if (length < 0)
{
JSONCONS_THROW(json_exception_impl<std::invalid_argument>("print_double failed."));
}
}
}
}
break;
}
const char* sbeg = number_buffer;
const char* send = sbeg + length;
const char* pexp = send;
if (sbeg != send)
{
bool dot = false;
for (pexp = sbeg; *pexp != 'e' && *pexp != 'E' && pexp < send; ++pexp)
{
}
for (const char* q = sbeg; q < pexp; ++q)
{
switch (*q)
{
case '-':case '0':case '1':case '2':case '3':case '4':case '5':case '6':case '7':case '8':case '9':
writer.put(*q);
break;
default:
if (*q == decimal_point_)
{
dot = true;
writer.put('.');
}
break;
}
}
if (!dot)
{
writer.put('.');
writer.put('0');
dot = true;
}
for (const char* q = pexp; q < send; ++q)
{
writer.put(*q);
}
}
}