context not cleaned at the end of a loop containing yield?

[TP]

Hi everybody,

This example gives strange results:

########
def foo( l = [] ):

    l2 = l
    print l2
    for i in range(10):
        if i%2 == 0:
            l2.append( i )
        yield i
########

>>> [i for i in ut.foo()]
[]
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> [i for i in ut.foo()]
[0, 2, 4, 6, 8]
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> [i for i in ut.foo()]
[0, 2, 4, 6, 8, 0, 2, 4, 6, 8]
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
...

How to explain this behavior? Why l is not [] when we enter again the
function foo()?

Thanks

Julien

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