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Lexical Conventions

The following conventions must be followed when entering XLISP programs:

Comments in XLISP code begin with a semi-colon character and continue to the end of the line.

Symbol names in XLISP can consist of any sequence of non-blank printable characters except the following:

( ) ' ` , " ;

Uppercase and lowercase characters are not distinguished within symbol names. All lowercase characters are mapped to uppercase on input.

Integer literals consist of a sequence of digits optionally beginning with a '+' or '-'. The range of values an integer can represent is limited by the size of a C 'long' on the machine on which XLISP is running.

Floating point literals consist of a sequence of digits optionally beginning with a '+' or '-' and including an embedded decimal point. The range of values a floating point number can represent is limited by the size of a C 'float' ('double' on machines with 32 bit addresses) on the machine on which XLISP is running.

Literal strings are sequences of characters surrounded by double quotes. Within quoted strings the '\' character is used to allow non-printable characters to be included. The codes recognized are:

\\       means the character '\'
\n       means newline
\t       means tab
\r       means return
\f       means form feed
\nnn     means the character whose octal code is nnn

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