..

original commit: 1abf2ac850c888bcb5b615981f7da52c85932165

collects/framework/framework.ss

@@ -1240,8 +1240,22 @@
     "That is, \\var{keymap} must be chained to some keymap attached"
     "to the editor.")
     
-
-    (scheme:add-preferences-panel
+   (scheme:text-balanced?
+    (opt->
+     ((is-a?/c text%))
+     (number? (union false? number?))
+     boolean?)
+   ((text)
+    ((start 0) (end #f)))
+   "Determines if the range in the editor from \\var{start} to \\var{end} in \\var{text}"
+   "is a matched set of parenthesis. If \\var{end} is \\scheme{#f}, it"
+   "defaults to the last position of the \\var{text}."
+   ""
+   "The implementation of this function creates a port with"
+   "@flink open-input-text-editor"
+   "and then uses `read' to parse the range of the buffer.")
+   
+   (scheme:add-preferences-panel
      (-> void?)
      ()
      "Adds a tabbing preferences panel to the preferences dialog.")

collects/framework/private/comment-box.ss

@@ -38,11 +38,24 @@
             (cons (keymap:get-file) (super-get-keymaps)))
           (super-instantiate ())))
       
+      (define scheme+copy-self% #f)
+      (define (get-scheme+copy-self%)
+        (unless scheme+copy-self%
+          (set! scheme+copy-self%
+                (class scheme:text%
+                  (inherit copy-self-to)
+                  (define/override (copy-self)
+                    (let ([ed (new scheme+copy-self%)])
+                      (copy-self-to ed)
+                      ed))
+                  (super-new))))
+        scheme+copy-self%)
+      
       (define -snip%
         (class* decorated-editor-snip% (readable-snip<%>)
           (inherit get-editor get-style)
           
-          (define/override (make-editor) (new scheme:text%))
+          (define/override (make-editor) (new (get-scheme+copy-self%)))
           (define/override (make-snip) (make-object -snip%))
           (define/override (get-corner-bitmap) bm)
           (define/override (get-position) 'left-top)

collects/framework/private/scheme.ss

@@ -43,6 +43,16 @@
               [-text% text%])
       
       
+      (define text-balanced? 
+        (opt-lambda (text [start 0] [in-end #f])
+          (let* ([end (or in-end (send text last-position))]
+                 [port (open-input-text-editor text start end)])
+            (with-handlers ([exn:read:eof? (lambda (x) #f)])
+              (let loop ()
+                (let ([s (read port)])
+                  (or (eof-object? s)
+                      (loop))))))))
+      
       ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
       ;;                                                                  ;;
       ;;                           Sexp Snip                              ;;

collects/framework/private/sig.ss

@@ -522,7 +522,9 @@
      
      get-color-prefs-table
      short-sym->pref-name
-     short-sym->style-name))
+     short-sym->style-name
+     
+     text-balanced?))
   (define-signature framework:scheme^
     ((open framework:scheme-class^)
      (open framework:scheme-fun^)))

collects/framework/private/standard-menus-items.ss

@@ -358,7 +358,7 @@
           (make-an-item 'edit-menu 'replace-and-find-again 
                         '(string-constant replace-and-find-again-info)
                         '(lambda (item control) (void))
-                        #\h 
+                        '(if (eq? (system-type) 'macosx) #f #\h)
                         '(string-constant replace-and-find-again-menu-item)
                         edit-menu:edit-target-on-demand
                         #f)