# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1256515418 -3600
# Node ID ed407c965ea509dd8f12d01cb38623b3f9d482be
# Parent  9f3f7c6148d8d564c34a88e4710576259350da3c
Added comments, Attr.exposes_name method.

diff -r 9f3f7c6148d8 -r ed407c965ea5 micropython/data.py
--- a/micropython/data.py	Mon Oct 26 00:26:07 2009 +0100
+++ b/micropython/data.py	Mon Oct 26 01:03:38 2009 +0100
@@ -304,6 +304,9 @@
         self.attributes_used.add(attrname)
         return self.attributes_used
 
+    def exposes_name(self, attrname):
+        return attrname in self.attributes_used
+
     # Value-related methods.
 
     def get_contexts(self):
diff -r 9f3f7c6148d8 -r ed407c965ea5 micropython/inspect.py
--- a/micropython/inspect.py	Mon Oct 26 00:26:07 2009 +0100
+++ b/micropython/inspect.py	Mon Oct 26 01:03:38 2009 +0100
@@ -198,13 +198,20 @@
         "Vacuum the given object 'obj'."
 
         for name, attr in obj.items():
+
+            # Only consider deleting entire unused objects or things accessible
+            # via names which are never used.
+
             if delete_all or not self.importer.uses_name(name):
                 del obj[name]
+
+                # Delete any unambiguous attribute value. Such values can only
+                # have been defined within the object and therefore are not
+                # redefined by other code regions.
+
                 if attr.assignments == 1:
                     value = attr.get_value()
 
-                    # Delete any unambiguous attribute value.
-
                     if value is not obj and value in self.all_objects:
                         self.all_objects.remove(value)