simplify buttons file

beautiful-racket/br/demo/jsonic-2/buttons.rkt

@@ -1,17 +1,18 @@
 #lang br
 (require racket/draw)
-(provide make-buttons)
+(provide make-button)
 
-(define make-buttons
-  (list (let ([label "Insert expression"]
-              [bitmap (make-object bitmap% 16 16)]
-              [callback (λ (drr-frame)
+(define label "Insert expression")
+(define bitmap (make-object bitmap% 16 16))
+(define (callback drr-frame)
   (define drr-editor (send drr-frame get-definitions-text))
   (define block-string "@$  $@")
   (send drr-editor begin-edit-sequence)
   (send drr-editor insert block-string)
   (send drr-editor end-edit-sequence)
   (define pos (send drr-editor get-end-position))
-                          (send drr-editor set-position (- pos (/ (string-length block-string) 2))))]
-              [number 98])
-          (list label bitmap callback number))))
+  (send drr-editor set-position (- pos (/ (string-length block-string) 2))))
+(define number 98)
+
+(define make-button
+  (list (list label bitmap callback number)))

beautiful-racket/br/demo/jsonic-2/main.rkt

@@ -10,7 +10,7 @@
         [(drracket:indentation)
          (dynamic-require 'br/demo/jsonic-2/indenter 'indent-jsonic)]
         [(drracket:toolbar-buttons)
-         (dynamic-require 'br/demo/jsonic-2/buttons 'make-buttons)]
+         (dynamic-require 'br/demo/jsonic-2/buttons 'make-button)]
         [else default]))
     handle-query))