use newlines in lexer

beautiful-racket-demo/basic-demo/expander.rkt

@@ -20,8 +20,8 @@
                                   #:source #'LINE-NUMBER)]
        [ORIG-LOC caller-stx])
     (syntax/loc caller-stx
-      (define (LINE-NUMBER-ID #:srcloc? [srcloc #f])
+      (define (LINE-NUMBER-ID #:srcloc? [loc #f])
-        (if srcloc
+        (if loc
             (syntax-srcloc #'ORIG-LOC)
             (begin (void) STATEMENT ...))))))
 

beautiful-racket-demo/basic-demo/lexer-test.rkt

@@ -11,8 +11,10 @@
                      (srcloc 'string #f #f 1 1))))
 (check-equal?
  (lex "rem ignored\n")
- (list (srcloc-token (token 'REM "rem ignored\n")
+ (list (srcloc-token (token 'REM "rem ignored")
-                     (srcloc 'string #f #f 1 12))))
+                     (srcloc 'string #f #f 1 11))
+       (srcloc-token (token 'NEWLINE)
+                     (srcloc 'string #f #f 12 1))))
 (check-equal?
  (lex "print")
  (list (srcloc-token "print"

beautiful-racket-demo/basic-demo/lexer.rkt

@@ -7,7 +7,7 @@
   (lexer-srcloc
    [(eof) (return-without-srcloc eof)]
    [(from/stop-before "rem" "\n") (token 'REM lexeme)]
-   [(:seq "\n" digits) (token 'LINE-NUMBER (string->number (string-trim lexeme)))] 
+   ["\n" (token 'NEWLINE)]
    [whitespace (token lexeme #:skip? #t)]
    [(:or "print" "goto" "end" "+" ":") lexeme]
    [digits (token 'INTEGER (string->number lexeme))]

beautiful-racket-demo/basic-demo/parser.rkt

@@ -1,7 +1,7 @@
 #lang brag
-b-program : b-line*
+b-program : [b-line] (/NEWLINE+ [b-line])*
 b-line : @b-line-number [b-statement] (/":" [b-statement])*
-b-line-number : LINE-NUMBER
+b-line-number : INTEGER
 @b-statement : b-rem
              | b-print
              | b-goto