Finding closures through introspection

[Steven D'Aprano]

On Mon, 14 Jun 2010 20:46:28 -0700, John Nagle wrote:

> So how can I detect a closure?

I *think* you do it through the co_flags attribute of the code object. 
This is in Python 2.5:


>>> def f(x):
...     def g():
...             return x
...     return g
...
>>>
>>> closure = f(42)
>>> closure()
42
>>> closure.func_code.co_flags
19
>>> f.func_code.co_flags
3


although this doesn't seem to be documented, at least not here:

http://docs.python.org/reference/datamodel.html



-- 
Steven