[Zope-CVS] CVS: Packages/pypes/pypes - expression.py:1.4

[Casey Duncan]

Update of /cvs-repository/Packages/pypes/pypes
In directory cvs.zope.org:/tmp/cvs-serv25525

Modified Files:
	expression.py 
Log Message:
Add helper function to compare ast nodes


=== Packages/pypes/pypes/expression.py 1.3 => 1.4 ===
--- Packages/pypes/pypes/expression.py:1.3	Sat Jan 31 00:23:30 2004
+++ Packages/pypes/pypes/expression.py	Sat Jan 31 01:09:26 2004
@@ -94,6 +94,28 @@
         return "Expression('%s')" % self._expr
     
     __repr__ = __str__
+    
+def nodesEqual(node1, node2):
+    """Return true if node1 and node2 are equivilant ast nodes. This is
+    a workaround for the fact that ast nodes themselves do not implement
+    comparison
+    """
+    if isinstance(node1, ast.Node) and isinstance(node2, ast.Node):
+        if node1.__class__ is node2.__class__:
+            children1 = node1.getChildren()
+            children2 = node2.getChildren()
+            if isinstance(children1, tuple) and isinstance(children2, tuple):
+                if len(children1) != len(children2):
+                    return False
+                for c1, c2 in zip(children1, children2):
+                    if not nodesEqual(c1, c2):
+                        return False
+                return True
+            else:
+                return children1 == children2
+        else:
+            return False
+    return node1 == node2            
 
 def getCallerNamespace(): 
     """Look up the stack fram and return a dict of the namespace of the code