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copied!<p>I feel Justice is plain right in his reasoning here.</p> <p>On the other hand -- I can't resist implementing proof of concept for still another programing paradigm "unnatural" to Python -- I simply love doing this. :-)</p> <p>So, I created a class whose objects'attributes are scopped just like you require (and can be created dynamically). As I said, it is just in a proof of concept state - but I think most usual errors, (like trying to access a variable ina scope it is not defined at all) should have errors raised, even if not the proper ones (IndexError due to a stack underflow instead of AttributeError, for example)</p> <pre><code>import inspect class DynamicVars(object): def __init__(self): object.__setattr__(self, "variables", {}) def normalize(self, stackframe): return [hash(tpl[0]) for tpl in stackframe[1:]] def __setattr__(self, attr, value): stack = self.normalize(inspect.stack()) d = {"value": value, "stack": stack} if not attr in self.variables: self.variables[attr] = [] self.variables[attr].append(d) else: our_value = self.variables[attr] if our_value[-1]["stack"] == stack: our_value[-1]["value"] = value elif len(stack) <= len(our_value): while our_value and stack != our_value["stack"]: our_value.pop() our_value.append(d) else: #len(stack) > len(our_value): our_value.append(d) def __getattr__(self, attr): if not attr in self.variables: raise AttributeError stack = self.normalize(inspect.stack()) while self.variables[attr]: our_stack = self.variables[attr][-1]["stack"] if our_stack == stack[-len(our_stack):]: break self.variables[attr].pop() else: raise AttributeError return self.variables[attr][-1]["value"] # for testing: def c(): D = DynamicVars() D.c = "old" print D.c def a(): print D.c a() def b(): D.c = "new" a() b() a() def c(): D.c = "newest" a() b() a() c() a() c() </code></pre>

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