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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Tue, 31 May 2011 16:24:27 -0600
Subject: Re: Something is rotten in Denmark...
To: Python <python-list@python.org>
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:6762

On Tue, May 31, 2011 at 2:18 PM, harrismh777 <harrismh777@charter.net> wrot=
e:
> If I'm understanding that correctly, then that means lambda is working as
> designed, and that there are very subtle nuances to be aware of. In my
> little case
>
> =A0 (lambda n: i + n)
>
> =A0 ... if the =A0i =A0goes out of scope before the anonymous function ge=
ts called
> then we have a problem... or if =A0i =A0 as a reference is mutable or ref=
ers to
> a different object before the anonymous function is called then we have a
> problem?

Actually, if i merely goes out of scope, there is no problem.  It just
creates a closure.  It's only when the i within that scope is modified
that we run into problems.

In fact, in Python 3 the scope of a list comprehension variable is the
list comprehension itself, so in your original post i was already out
of scope by the time you started calling the lambda functions.

Cheers,
Ian