Unitized macro stepper view; tool uses different base frame

svn: r4309

original commit: c9653c888b189ce499617825385c5522c2c40634

collects/macro-debugger/expand.ss

@@ -1,6 +1,7 @@
 
 (module expand mzscheme
-  (require "view/gui.ss")
+  (require (lib "unitsig.ss"))
+  (require "view/view.ss")
   (provide expand/step)
 
   (define (expand/step stx)

collects/macro-debugger/view/view.ss

@@ -0,0 +1,13 @@
+
+(module view mzscheme
+  (require (lib "unitsig.ss"))
+  (require "gui.ss")
+  (provide (all-defined))
+
+  (define-values/invoke-unit/sig view^
+    (compound-unit/sig
+      (import)
+      (link (BASE : view-base^ (view-base@))
+            (VIEW : view^ (view@ BASE)))
+      (export (open VIEW))))
+  )