The ':mescape' keyword is an entry used in the *readtable* system variable that contains XLISP's data structures relating to the processing of characters from the user (or files) and read-macro expansions. The existance of the ':mescape' keyword means that the specified character is to be used as a multiple escape character. The system defines that the the vertical bar character '|' is the only ':mescape' character.
;; define a function to look in a table
;; and print out any :mescape character
(defun look-at (table)
(dotimes (ch 127)
(prog ((entry (aref table ch)))
(case entry
(:mescape (princ (int-char ch)))
(t nil))))
(terpri))
(look-at *readtable*) ; prints |
Caution: If you experiment with
See the
:mescape
keyword in the