LispEngine.Lexing.Scanner.unsignedNumber C# (CSharp) Method

        private static TokenType? unsignedNumber(Scanner s)
        {
            if (!s.isDigit())
                return null;
            while (s.isDigit())
                s.readChar();
            if (s.isExponent())
                return readExponent(s);
            if (s.peek() != '.')
                return TokenType.Integer;
            return remainingFloat(s);
        }