better

beautiful-racket-lib/br/indent.rkt

@@ -53,7 +53,7 @@
   (check-equal? (next-line t 11) #f))
 
 (define (valid-line? text line)
-  (<= 0 line (send text last-line)))
+  (and line (<= 0 line (send text last-line))))
 
 (define (line-start text line)
   (and (valid-line? text line)

beautiful-racket/br/demo/jsonic/indenter.rkt

@@ -3,19 +3,28 @@
 (provide indenter)
 (define indent-width 2)
 
-(define (indenter text start-pos)
+(define (indenter text this-pos)
   ;; if line begins with }:
   ;; outdent to the matching {
   ;; indent to match the previous line
-  (define the-line (line text start-pos))
-  (define line-last-pos (line-end text the-line))
+  (define this-line (line text this-pos))
+  (define this-line-end (line-end text this-line))
   (define open-braces
-    (- (count-char text #\{ 0 line-last-pos)
-       (count-char text #\} 0 line-last-pos)))
-  (define line-first-pos (line-start text the-line))
-  (define first-char (char text line-first-pos))
+    (- (count-char text #\{ 0 this-line-end)
+       (count-char text #\} 0 this-line-end)))
   (and (positive? open-braces)
        (* indent-width
-          (if (first-char . char=? . #\{)
+          (if ((char text (line-start text this-line)) . char=? . #\{)
               (sub1 open-braces)
               open-braces))))
+
+#|
+  (define prev-line (previous-line text this-line))
+  (define prev-indent (line-indent text prev-line))
+  (cond
+    [((char text (line-start text this-line)) . char=? . #\})
+     (and prev-indent (- prev-indent indent-width))]
+    [((char text (line-start text prev-line)) . char=? . #\{)
+     (+ (or prev-indent 0) indent-width)]
+    [else prev-indent]))
+|#