diff --git a/collects/macro-debugger/util/notify.ss b/collects/macro-debugger/util/notify.ss
index 37af75c0..c5c6e8c8 100644
--- a/collects/macro-debugger/util/notify.ss
+++ b/collects/macro-debugger/util/notify.ss
@@ -1,196 +1,196 @@
 
-(module notify mzscheme
-  (require (lib "list.ss")
-           (lib "class.ss")
-           (lib "mred.ss" "mred"))
-  (provide define/listen
-           field/notify
-           notify-methods
-           connect-to-pref
-           connect-to-pref/readonly
-           override/return-false
-           notify-box%
-           notify-box/pref
-           menu-option/notify-box
-           menu-group/notify-box
-           check-box/notify-box
-           choice/notify-box)
+#lang scheme/base
+(require (for-syntax scheme/base)
+         scheme/list
+         scheme/class
+         scheme/gui)
+(provide define/listen
+         field/notify
+         notify-methods
+         connect-to-pref
+         connect-to-pref/readonly
+         override/return-false
+         notify-box%
+         notify-box/pref
+         menu-option/notify-box
+         menu-group/notify-box
+         check-box/notify-box
+         choice/notify-box)
 
-  (define-for-syntax (join . args)
-    (define (->string x)
-      (cond [(string? x) x]
-            [(symbol? x) (symbol->string)]
-            [(identifier? x) (symbol->string (syntax-e x))]
-            [else (error '->string)]))
-    (string->symbol (apply string-append (map ->string args))))
+(define-for-syntax (join . args)
+  (define (->string x)
+    (cond [(string? x) x]
+          [(symbol? x) (symbol->string)]
+          [(identifier? x) (symbol->string (syntax-e x))]
+          [else (error '->string)]))
+  (string->symbol (apply string-append (map ->string args))))
 
-  (define-syntax override/return-false
-    (syntax-rules ()
-      [(override/return-false m ...)
-       (begin (define/override (m) #f) ...)]))
+(define-syntax override/return-false
+  (syntax-rules ()
+    [(override/return-false m ...)
+     (begin (define/override (m) #f) ...)]))
 
-  (define-syntax (field/notify stx)
-    (syntax-case stx ()
-      [(field/notify name value)
-       (with-syntax ([init-name
-                      (datum->syntax-object #'name (join "init-" #'name))]
-                     [get-name
-                      (datum->syntax-object #'name (join "get-" #'name))]
-                     [set-name
-                      (datum->syntax-object #'name (join "set-" #'name))]
-                     [listen-name
-                      (datum->syntax-object #'name (join "listen-" #'name))])
-         #'(begin (field [name (init-name)])
-                  (define/public (init-name) value)
-                  (define/public-final (get-name)
-                    (send name get))
-                  (define/public-final (set-name new-value)
-                    (send name set new-value))
-                  (define/public-final (listen-name listener)
-                    (send name listen listener))))]))
+(define-syntax (field/notify stx)
+  (syntax-case stx ()
+    [(field/notify name value)
+     (with-syntax ([init-name
+                    (datum->syntax #'name (join "init-" #'name))]
+                   [get-name
+                    (datum->syntax #'name (join "get-" #'name))]
+                   [set-name
+                    (datum->syntax #'name (join "set-" #'name))]
+                   [listen-name
+                    (datum->syntax #'name (join "listen-" #'name))])
+       #'(begin (field [name (init-name)])
+                (define/public (init-name) value)
+                (define/public-final (get-name)
+                  (send name get))
+                (define/public-final (set-name new-value)
+                  (send name set new-value))
+                (define/public-final (listen-name listener)
+                  (send name listen listener))))]))
 
-  (define-syntax (notify-methods stx)
-    (syntax-case stx ()
-      [(notify-methods name)
-       (with-syntax ([init-name
-                      (datum->syntax-object #'name (join "init-" #'name))]
-                     [get-name
-                      (datum->syntax-object #'name (join "get-" #'name))]
-                     [set-name
-                      (datum->syntax-object #'name (join "set-" #'name))]
-                     [listen-name
-                      (datum->syntax-object #'name (join "listen-" #'name))])
-         #'(begin (field [name (init-name)])
-                  (define/public (init-name)
-                    (new notify-box% (value #f)))
-                  (define/public-final (get-name)
-                    (send name get))
-                  (define/public-final (set-name new-value)
-                    (send name set new-value))
-                  (define/public-final (listen-name listener)
-                    (send name listen listener))))]))
-  
-  (define-syntax (connect-to-pref stx)
-    (syntax-case stx ()
-      [(connect-to-pref name pref)
-       (with-syntax ([init-name
-                      (datum->syntax-object #'name (join "init-" #'name))])
-         #'(define/override (init-name) (notify-box/pref pref)))]))
+(define-syntax (notify-methods stx)
+  (syntax-case stx ()
+    [(notify-methods name)
+     (with-syntax ([init-name
+                    (datum->syntax #'name (join "init-" #'name))]
+                   [get-name
+                    (datum->syntax #'name (join "get-" #'name))]
+                   [set-name
+                    (datum->syntax #'name (join "set-" #'name))]
+                   [listen-name
+                    (datum->syntax #'name (join "listen-" #'name))])
+       #'(begin (field [name (init-name)])
+                (define/public (init-name)
+                  (new notify-box% (value #f)))
+                (define/public-final (get-name)
+                  (send name get))
+                (define/public-final (set-name new-value)
+                  (send name set new-value))
+                (define/public-final (listen-name listener)
+                  (send name listen listener))))]))
 
-  (define-syntax (connect-to-pref/readonly stx)
-    (syntax-case stx ()
-      [(connect-to-pref/readonly name pref)
-       (with-syntax ([init-name
-                      (datum->syntax-object #'name (join "init-" #'name))])
-         #'(define/override (init-name) (notify-box/pref/readonly pref)))]))
+(define-syntax (connect-to-pref stx)
+  (syntax-case stx ()
+    [(connect-to-pref name pref)
+     (with-syntax ([init-name
+                    (datum->syntax #'name (join "init-" #'name))])
+       #'(define/override (init-name) (notify-box/pref pref)))]))
 
-  (define-syntax (define/listen stx)
-    (syntax-case stx ()
-      [(define/listen name value)
-       (unless (identifier? #'name)
-         (raise-syntax-error 'define/listen "expected identifier" #'name))
-       (with-syntax ([get-name
-                      (datum->syntax-object #'name (join "get-" #'name))]
-                     [set-name
-                      (datum->syntax-object #'name (join "set-" #'name))]
-                     [listen-name
-                      (datum->syntax-object #'name (join "listen-" #'name))])
-         #'(begin
-             (define name value)
-             (define listeners null)
-             (define/public-final (get-name) name)
-             (define/public-final (set-name new-value)
-               (set! name new-value)
-               (for-each (lambda (listener) (listener new-value)) listeners))
-             (define/public-final (listen-name listener)
-               (set! listeners (cons listener listeners)))))]))
+(define-syntax (connect-to-pref/readonly stx)
+  (syntax-case stx ()
+    [(connect-to-pref/readonly name pref)
+     (with-syntax ([init-name
+                    (datum->syntax #'name (join "init-" #'name))])
+       #'(define/override (init-name) (notify-box/pref/readonly pref)))]))
 
-  (define notify-box%
-    (class object%
-      (init value)
-      (define v value)
-      (define listeners null)
+(define-syntax (define/listen stx)
+  (syntax-case stx ()
+    [(define/listen name value)
+     (unless (identifier? #'name)
+       (raise-syntax-error 'define/listen "expected identifier" #'name))
+     (with-syntax ([get-name
+                    (datum->syntax #'name (join "get-" #'name))]
+                   [set-name
+                    (datum->syntax #'name (join "set-" #'name))]
+                   [listen-name
+                    (datum->syntax #'name (join "listen-" #'name))])
+       #'(begin
+           (define name value)
+           (define listeners null)
+           (define/public-final (get-name) name)
+           (define/public-final (set-name new-value)
+             (set! name new-value)
+             (for-each (lambda (listener) (listener new-value)) listeners))
+           (define/public-final (listen-name listener)
+             (set! listeners (cons listener listeners)))))]))
 
-      ;; get : -> value
-      ;; Fetch current value
-      (define/public (get)
-        v)
+(define notify-box%
+  (class object%
+    (init value)
+    (define v value)
+    (define listeners null)
 
-      ;; set : value -> void
-      ;; Update value and notify listeners
-      (define/public (set nv)
-        (set! v nv)
-        (for-each (lambda (p) (p nv)) listeners))
+    ;; get : -> value
+    ;; Fetch current value
+    (define/public (get)
+      v)
 
-      ;; listen : (value -> void) -> void
-      ;; Add a listener
-      (define/public (listen p)
-        (set! listeners (cons p listeners)))
+    ;; set : value -> void
+    ;; Update value and notify listeners
+    (define/public (set nv)
+      (set! v nv)
+      (for-each (lambda (p) (p nv)) listeners))
 
-      ;; remove-listener : (value -> void) -> void
-      (define/public (remove-listener p)
-        (set! listeners (remq p listeners)))
+    ;; listen : (value -> void) -> void
+    ;; Add a listener
+    (define/public (listen p)
+      (set! listeners (cons p listeners)))
 
-      ;; remove-all-listeners : -> void
-      (define/public (remove-all-listeners)
-        (set! listeners null))
+    ;; remove-listener : (value -> void) -> void
+    (define/public (remove-listener p)
+      (set! listeners (remq p listeners)))
 
-      (super-new)))
+    ;; remove-all-listeners : -> void
+    (define/public (remove-all-listeners)
+      (set! listeners null))
 
-  (define (notify-box/pref pref)
-    (define nb (new notify-box% (value (pref))))
-    (send nb listen pref)
-    nb)
+    (super-new)))
 
-  (define (notify-box/pref/readonly pref)
-    (new notify-box% (value (pref))))
+(define (notify-box/pref pref)
+  (define nb (new notify-box% (value (pref))))
+  (send nb listen pref)
+  nb)
 
-  (define (menu-option/notify-box parent label nb)
-    (define menu-item
-      (new checkable-menu-item%
-           (label label)
-           (parent parent)
-           (checked (send nb get))
-           (callback
-            (lambda _ (send nb set (send menu-item is-checked?))))))
-    (send nb listen (lambda (value) (send menu-item check value)))
-    menu-item)
+(define (notify-box/pref/readonly pref)
+  (new notify-box% (value (pref))))
 
-  (define (check-box/notify-box parent label nb)
-    (define checkbox
-      (new check-box%
-           (label label)
-           (parent parent)
-           (value (send nb get))
-           (callback
-            (lambda (c e) (send nb set (send c get-value))))))
-    (send nb listen (lambda (value) (send checkbox set-value value)))
-    checkbox)
+(define (menu-option/notify-box parent label nb)
+  (define menu-item
+    (new checkable-menu-item%
+         (label label)
+         (parent parent)
+         (checked (send nb get))
+         (callback
+          (lambda _ (send nb set (send menu-item is-checked?))))))
+  (send nb listen (lambda (value) (send menu-item check value)))
+  menu-item)
 
-  (define (choice/notify-box parent label choices nb)
-    (define choice
-      (new choice%
-           (label label)
-           (parent parent)
-           (style '(horizontal-label))
-           (choices choices)
-           (callback (lambda (c e) (send nb set (send c get-string-selection))))))
-    (send choice set-string-selection (send nb get))
-    (send nb listen (lambda (value) (send choice set-string-selection value)))
-    choice)
+(define (check-box/notify-box parent label nb)
+  (define checkbox
+    (new check-box%
+         (label label)
+         (parent parent)
+         (value (send nb get))
+         (callback
+          (lambda (c e) (send nb set (send c get-value))))))
+  (send nb listen (lambda (value) (send checkbox set-value value)))
+  checkbox)
 
-  (define (menu-group/notify-box parent labels nb)
-    (map (lambda (option)
-           (define label (if (pair? option) (car option) option))
-           (define menu-item
-             (new checkable-menu-item%
-                  (label label)
-                  (parent parent)
-                  (checked (eq? (send nb get) option))
-                  (callback
-                   (lambda _ (send nb set option)))))
-           (send nb listen
-                 (lambda (value) (send menu-item check (eq? value option))))
-           menu-item)
-         labels))
-  )
+(define (choice/notify-box parent label choices nb)
+  (define choice
+    (new choice%
+         (label label)
+         (parent parent)
+         (style '(horizontal-label))
+         (choices choices)
+         (callback (lambda (c e) (send nb set (send c get-string-selection))))))
+  (send choice set-string-selection (send nb get))
+  (send nb listen (lambda (value) (send choice set-string-selection value)))
+  choice)
+
+(define (menu-group/notify-box parent labels nb)
+  (map (lambda (option)
+         (define label (if (pair? option) (car option) option))
+         (define menu-item
+           (new checkable-menu-item%
+                (label label)
+                (parent parent)
+                (checked (eq? (send nb get) option))
+                (callback
+                 (lambda _ (send nb set option)))))
+         (send nb listen
+               (lambda (value) (send menu-item check (eq? value option))))
+         menu-item)
+       labels))