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

        private static TokenType? readExponent(Scanner s)
        {
            s.readChar(); // Skip exponent market
            var read = false;
            if (s.isOneOf("+-"))
            {
                s.readChar();
                read = true;
            }
            while (s.isDigit())
            {
                read = true;
                s.readChar();
            }
            if(read)
                return TokenType.Double;
            // It's not a floating point number in exponent format.
            // Read it as a symbol instead.
            matchSymbol(s);
            return TokenType.Symbol;
        }