at-exp, scribble: remove distinctness of @{}-introduced newlines

collects/scribble/reader.rkt

@@ -154,11 +154,9 @@
                 (+ w (if (eq? 9 (bytes-ref bs i)) (- 8 (modulo w 8)) 1))))))))
 
 ;; a unique eol string
-(define eol-token "\n")
-(define (eol-syntax? x) (and (syntax? x) (eq? eol-token (syntax-e x))))
-;; sanity check, in case this property gets violated in the future
-(unless (eol-syntax? (datum->syntax #f eol-token))
-  (internal-error 'invalid-assumption))
+(define at-exp-prop (gensym 'at-exp-eol))
+(define (eol-syntax? x) 
+  (and (syntax? x) (syntax-property x at-exp-prop)))
 
 ;; A syntax object that has the "original?" property:
 (define orig-stx (read-syntax #f (open-input-string "dummy")))
@@ -265,8 +263,8 @@
     (let* ([2nd  (and (syntax? stx) (syntax-e stx))]
            [stx0 (and (pair? stxs) (car stxs))]
            [1st  (and (syntax? stx0) (syntax-e stx0))])
-      (if (and (string? 1st) (not (eq? eol-token 1st))
-               (string? 2nd) (not (eq? eol-token 2nd)))
+      (if (and (string? 1st) (not (eol-syntax? stx0))
+               (string? 2nd) (not (eol-syntax? stx)))
         (cons (datum->syntax stx0
                 (string-append 1st 2nd)
                 (vector (syntax-source stx0)
@@ -318,7 +316,7 @@
                 (loop lvl (list* ; no merge needed
                            (bytes-width m (cdr n))
                            (syntax-property
-                            (make-stx eol-token)
+                            (syntax-property (make-stx "\n") at-exp-prop #t)
                             'scribble `(newline ,(bytes->string/utf-8 m)))
                            (maybe-drop-marker r)))))]
         [(if re:cmd-pfx

collects/scribblings/scribble/reader.scrbl

@@ -629,29 +629,6 @@ newlines are read as a @racket["\n"] string
        baz }
 }===|
 
-In the parsed S-expression syntax, a single newline string is used for
-all newlines; you can use @racket[eq?] to identify this line.  This
-can be used to identify newlines in the original @nonterm{text-body}.
-
-@; FIXME: unfortunate code duplication (again):
-@interaction[
-(eval:alts
-  (let ([nl (car @#,tt["@'{"]
-                 @#,tt["  }"])])
-    (for-each (lambda (x) (display (if (eq? x nl) "\n... " x)))
-              @#,tt["@`{foo"]
-              @#,elem[@tt["   @"] @racket[,@(list "bar" "\n" "baz")]]
-              @#,tt["   blah}}"])
-    (newline))
-  (let ([nl (car @'{
-                   })])
-    (for-each (lambda (x) (display (if (eq? x nl) "\n... " x)))
-              @`{foo
-                 @,@(list "bar" "\n" "baz")
-                 blah})
-    (newline)))
-]
-
 Spaces at the beginning of body lines do not appear in the resulting
 S-expressions, but the column of each line is noticed, and all-space
 indentation strings are added so the result has the same indentation.

collects/tests/scribble/reader.rkt

@@ -744,18 +744,6 @@ foo
 -@eval->
 "/Note/: *This is _not_ a pipe*."
 ---
-(let ([nl (car @'{
-                 })]
-      [o (open-output-string)])
-  (for-each (lambda (x) (display (if (eq? x nl) "\n... " x) o))
-            @`{foo
-               @,@(list "bar" "\n" "baz")
-               blah})
-  (newline o)
-  (get-output-string o))
--@eval->
-"foo\n... bar\nbaz\n... blah\n"
----
 (require (for-syntax scheme/base))
 (let-syntax ([foo
               (lambda (stx)

doc/release-notes/racket/HISTORY.txt

@@ -8,6 +8,7 @@ racket/draw: added get-names to color-database<%>
 mzlib/pconvert: added add-make-prefix-to-constructor parameter,
  which changes the default constructor-style printing in DrRacket
  to avoid a make- prefix; the HtDP languages set the parameter to #t
+at-exp, scribble: dropped distinctness of @{}-introduced newline strings
 
 Version 5.2.0.3
 Added module-predefined?