# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1340145843 -7200
# Node ID 1b42eee2b7499784889dc0158439d4b570bba342
# Parent  ea25b91e1adc9867c719b58219303b6517dcbed2
Changed attribute usage recording to apply only to function and class definition locals.

diff -r ea25b91e1adc -r 1b42eee2b749 docs/concepts.txt
--- a/docs/concepts.txt	Tue Jun 19 00:29:57 2012 +0200
+++ b/docs/concepts.txt	Wed Jun 20 00:44:03 2012 +0200
@@ -45,6 +45,58 @@
 See rejected.txt for complicating mechanisms which could be applied to
 mitigate the effects of these restrictions on optimisations.
 
+Attribute Usage Observations
+============================
+
+Within a scope, a name may be used in conjunction with attribute names in
+order to access attributes on objects referenced by the name. However, such
+observations can only be regarded as reliable if the object referenced is not
+changed independently by some other mechanism or activity.
+
+With conventional functions and methods, any locally defined names can be
+considered private to that scope and thus immune to independent modification,
+at least within reasonable features of the language. Although stack
+modification may be possible, it seems appropriate to reject such features,
+especially since they lend themselves to unmaintainable programs.
+
+For names defined during the initialisation of a class, since the class itself
+cannot be referenced by name until its declaration has been completely
+evaluated, no independent modification can occur from outside the class scope.
+
+For names defined during the initialisation of a module, global declarations
+in functions permit the rebinding of global variables and since functions may
+be invoked during module initialisation, independent modification can
+potentially occur if any functions are called.
+
+Module globals can be accessed from other modules that can refer to a module
+by its name. Initially, an import is required to make a module available for
+modification, but there is no restriction on whether a module has been
+completely imported (and thus defined) before an import statement can make it
+available to other modules. Consider the following package root definition:
+
+    # Module test:
+    def f():
+        import test.modifier
+    x = 123
+    f()
+
+    # Module test.modifier:
+    import test
+    test.x = 456
+
+Here, an import of test will initially set x to 123, but then the function f
+will be invoked and cause the test.modifier module to be imported. Since the
+test module is already being imported, the import statement will not try to
+perform the import operation again, but it will make the partially defined
+module available for access. Thus, the test.modifier module will then set x to
+456, and independent modification of the test namespace will have been
+performed.
+
+In conclusion, module globals cannot therefore be regarded as immune to
+operations that would disrupt usage observations. Consequently, only locals
+and class definition "locals" can be reliably employed in attribute usage
+observations. 
+
 Contexts and Values
 ===================
 
diff -r ea25b91e1adc -r 1b42eee2b749 micropython/inspect.py
--- a/micropython/inspect.py	Tue Jun 19 00:29:57 2012 +0200
+++ b/micropython/inspect.py	Wed Jun 20 00:44:03 2012 +0200
@@ -582,9 +582,11 @@
         where such attributes are inferred from the usage.
         """
 
-        # Access to attribute via a local.
+        # Access to attribute via a local in functions or classes but not
+        # modules (since module-level locals are globals that can be modified
+        # independently of the namespace).
 
-        if expr.parent is self.get_namespace():
+        if expr.parent is self.get_namespace() and not self.get_namespace() is self:
 
             # NOTE: Revisiting of nodes may occur for loops.
 
diff -r ea25b91e1adc -r 1b42eee2b749 tests/attribute_access_type_restriction_global_reassigned.py
--- a/tests/attribute_access_type_restriction_global_reassigned.py	Tue Jun 19 00:29:57 2012 +0200
+++ b/tests/attribute_access_type_restriction_global_reassigned.py	Wed Jun 20 00:44:03 2012 +0200
@@ -36,11 +36,12 @@
 obj = d
 
 if obj.f():
+    obj.g()
     change_global()
-    x = obj.g()
+    x = obj.f()
 else:
     x = 2
 
-result_3 = x
+result_4 = x
 
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