;;; file for checking that escape characters are working as expected

%(letter-set (!p !?))
%(letter-set (!f ~`!@#$%^&*(\)-_=+{}[]|\\;:'",<.>/?\1))

;;; (show-letter-sets) should give
;;; !F (~ ` ! @ # $ % ^ & * ( ) - _ = + { } [ ] | \ ; : ' " , < . > / ? 1)
;;; no spaces, ) has to be escaped with \ -  \ has to be \\
;;; escaping other characters is harmless - \ is just ignored
;;; everything ends up upper case

;;; letter set names must be a single character - they can be anything other
;;; than ?!)* or \.  They should not have escape characters in them when 
;;; they occur.

escape :=
%suffix (* ~`\!@#$%^&\*(\)-_=+{}[]|\\;:'",<.>/\?\1)
[ CATEG cat2,
  ARGS < [ CATEG cat1 ] > ].

;;; rule above is for testing escape - ?!)* have to be escaped by \
;;; for \ use \\.  other characters may be escaped without harm
;;; should return
;;; ESCAPE SUFFIX       UNDERLYING / SURFACE
;;;                     / ~`!@#$%^&*()-_=+{}[]|\;:'",<.>/?1