# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1312742304 -7200
# Node ID 95e3c8b48a1d499d0a03941c2cd2aa460863a4ac
# Parent  1c036da5aff9b4ecb2ce8371e00239754f1bbb9c
Replaced Instance instantiation with usage of a function that obtains a common
instance of the class.

diff -r 1c036da5aff9 -r 95e3c8b48a1d micropython/data.py
--- a/micropython/data.py	Sun Aug 07 19:23:49 2011 +0200
+++ b/micropython/data.py	Sun Aug 07 20:38:24 2011 +0200
@@ -238,7 +238,7 @@
 
         if value is None:
             print "Warning: name %r in namespace %r has an unknown value (evaluated to None)." % (name, self.full_name())
-            value = Instance()
+            value = make_instance()
 
         if name in self.globals:
             self.module.set(name, value, 0)
@@ -933,7 +933,7 @@
         """
 
         if self.context_values.issuperset(context_values) and \
-            not (Instance(), Instance()) in context_values:
+            not (make_instance(), make_instance()) in context_values:
             return
 
         if self.assignments is None:
@@ -1098,6 +1098,11 @@
 
     __shortrepr__ = __repr__
 
+common_instance = Instance()
+
+def make_instance():
+    return common_instance
+
 class Constant:
 
     "A superclass for all constant or context-free structures."
@@ -1462,7 +1467,7 @@
 
         d = {}
         for i, name in enumerate(self._get_position_list(instattr)):
-            d[name] = Attr(i, Instance(), name)
+            d[name] = Attr(i, make_instance(), name)
         return d
 
     def _get_position_list(self, positions):
@@ -1645,11 +1650,11 @@
         "Add 'argnames' to the namespace."
 
         for name in argnames:
-            self.set(name, Instance())
+            self.set(name, make_instance())
 
         for name, top_level in self._flattened_parameters(argnames):
             if not top_level:
-                self.set(name, Instance())
+                self.set(name, make_instance())
 
     def _flattened_parameters(self, argnames, top_level=1):
         l = []
@@ -1718,7 +1723,7 @@
         name = "<context>"
         self.argnames.insert(0, name)
         self.positional_names.insert(0, name)
-        self.set(name, Instance())
+        self.set(name, make_instance())
 
     # Namespace-related methods.
 
diff -r 1c036da5aff9 -r 95e3c8b48a1d micropython/inspect.py
--- a/micropython/inspect.py	Sun Aug 07 19:23:49 2011 +0200
+++ b/micropython/inspect.py	Sun Aug 07 20:38:24 2011 +0200
@@ -171,7 +171,7 @@
             if isinstance(n, compiler.ast.Global):
                 for name in n.names:
                     if not self.has_key(name):
-                        self[name] = Instance()
+                        self[name] = make_instance()
             else:
                 self.process_globals(n)
 
@@ -427,7 +427,7 @@
     def OP(self, node):
         for n in node.getChildNodes():
             self.dispatch(n)
-        return Instance()
+        return make_instance()
 
     # Generic support for classes of operations.
 
@@ -468,21 +468,21 @@
                 if attrname == "__class__" and isinstance(value, Class):
                     attr = type_class
                 else:
-                    attr = value.get(attrname) or Instance()
+                    attr = value.get(attrname) or make_instance()
                 self.use_specific_attribute(value.full_name(), attrname)
 
             elif isinstance(value, UnresolvedName):
                 attr = UnresolvedName(attrname, value.full_name(), self)
 
             else:
-                attr = Instance()
+                attr = make_instance()
 
                 # Note usage of the attribute where a local is involved.
 
                 self._visitAttrUser(expr, attrname, node)
 
         else:
-            attr = Instance()
+            attr = make_instance()
             self.use_name(attrname, node)
 
         return attr
@@ -851,7 +851,7 @@
         # NOTE: Could generate AST nodes for the actual operations instead of
         # NOTE: manually generating code in micropython.ast.
 
-        self.expr = Instance() # each element is a result of a function call
+        self.expr = make_instance() # each element is a result of a function call
         self.dispatch(node.assign)
 
         # Enter the loop.
@@ -972,7 +972,7 @@
         self.shelve_branch()
 
         self.merge_branches()
-        return Instance() # either outcome is possible
+        return make_instance() # either outcome is possible
 
     def visitImport(self, node):
         for name, alias in node.names:
@@ -1005,7 +1005,7 @@
         for qual in node.quals:
             self.dispatch(qual)
         self.dispatch(node.expr)
-        return Instance()
+        return make_instance()
 
     def visitListCompFor(self, node):
         self.new_branchpoint()
@@ -1022,7 +1022,7 @@
         # NOTE: Could generate AST nodes for the actual operations instead of
         # NOTE: manually generating code in micropython.ast.
 
-        self.expr = Instance() # each element is a result of a function call
+        self.expr = make_instance() # each element is a result of a function call
         self.dispatch(node.assign)
 
         # Enter the loop.
@@ -1052,7 +1052,7 @@
     visitMul = _visitBinary
 
     def visitName(self, node):
-        return self.get_namespace().get_using_node(node.name, node) or Instance()
+        return self.get_namespace().get_using_node(node.name, node) or make_instance()
 
     visitNot = OP