Use the character Comparison functions Decimal Digit?, Hex Digit?, Octal Digit?, Printable?, White Space?, and Lexical Class to compare characters to determine the type of a character.
If the input to the Comparison function is a string, the functions test the first character. If the input is an empty string, the result is FALSE. If the input is a number, the functions interpret it as an ASCII character code. If the input is a floating-point number, the function rounds to the nearest integer.