private void ReadSpecialToken()
{
var start = _position;
var end = _position;
_currentIdentifierChars.Clear();
// We track an identifier to check if it is a keyword (inf, true, false)
var firstChar = _c;
_currentIdentifierChars.Add(_c);
NextChar();
// IF we have a digit, this is a -1 or +2
if ((firstChar == '+' || firstChar == '-') && CharHelper.IsDigit(_c))
{
_currentIdentifierChars.Clear();
ReadNumberOrDate(firstChar, start);
return;
}
while (CharHelper.IsIdentifierContinue(_c))
{
// We track an identifier to check if it is a keyword (inf, true, false)
_currentIdentifierChars.Add(_c);
end = _position;
NextChar();
}
if (MatchCurrentIdentifier("true"))
{
_token = new SyntaxTokenValue(TokenKind.True, start, end, BoxedValues.True);
}
else if (MatchCurrentIdentifier("false"))
{
_token = new SyntaxTokenValue(TokenKind.False, start, end, BoxedValues.False);
}
else if (MatchCurrentIdentifier("inf"))
{
_token = new SyntaxTokenValue(TokenKind.Infinite, start, end, BoxedValues.FloatPositiveInfinity);
}
else if (MatchCurrentIdentifier("+inf"))
{
_token = new SyntaxTokenValue(TokenKind.PositiveInfinite, start, end, BoxedValues.FloatPositiveInfinity);
}
else if (MatchCurrentIdentifier("-inf"))
{
_token = new SyntaxTokenValue(TokenKind.NegativeInfinite, start, end, BoxedValues.FloatNegativeInfinity);
}
else if (MatchCurrentIdentifier("nan"))
{
_token = new SyntaxTokenValue(TokenKind.Nan, start, end, BoxedValues.FloatNan);
}
else if (MatchCurrentIdentifier("+nan"))
{
_token = new SyntaxTokenValue(TokenKind.PositiveNan, start, end, BoxedValues.FloatPositiveNaN);
}
else if (MatchCurrentIdentifier("-nan"))
{
_token = new SyntaxTokenValue(TokenKind.NegativeNan, start, end, BoxedValues.FloatNegativeNaN);
}
else
{
_token = new SyntaxTokenValue(TokenKind.Invalid, start, end);
}
_currentIdentifierChars.Clear();
}