CJsonNode CJsonNode::GuessType(const CTempString& value)
{
const char* ch = value.begin();
const char* end = value.end();
switch (*ch) {
case '"':
case '\'':
return NewStringNode(NStr::ParseQuoted(value));
case '-':
if (++ch >= end || !isdigit(*ch))
return NewStringNode(value);
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
do
if (++ch >= end)
return NewIntegerNode(NStr::StringToInt8(value));
while (isdigit(*ch));
switch (*ch) {
case '.':
if (++ch == end || !isdigit(*ch))
return NewStringNode(value);
for (;;) {
if (++ch == end)
return NewDoubleNode(NStr::StringToDouble(value));
if (!isdigit(*ch)) {
if (*ch == 'E' || *ch == 'e')
break;
return NewStringNode(value);
}
}
/* FALL THROUGH */
case 'E':
case 'e':
if (++ch < end && (*ch == '-' || *ch == '+' ?
++ch < end && isdigit(*ch) : isdigit(*ch)))
do
if (++ch == end)
return NewDoubleNode(NStr::StringToDouble(value));
while (isdigit(*ch));
/* FALL THROUGH */
default:
return NewStringNode(value);
}
}
return NStr::CompareNocase(value, "false") == 0 ? NewBooleanNode(false) :
NStr::CompareNocase(value, "true") == 0 ? NewBooleanNode(true) :
NStr::CompareNocase(value, "none") == 0 ? NewNullNode() :
NewStringNode(value);
}
static bool IsInteger(const CTempString& value)
{
if (value.empty())
return false;
const char* digit = value.end();
while (--digit > value.begin())
if (!isdigit(*digit))
return false;
return isdigit(*digit) || (*digit == '-' && value.length() > 1);
}