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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Sat, 29 Jun 2013 23:46:12 -0600
Subject: Re: Closures in leu of pointers?
To: Python <python-list@python.org>
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On Sat, Jun 29, 2013 at 10:32 PM, Terry Reedy <tjreedy@udel.edu> wrote:
> On 6/29/2013 5:21 PM, Ian Kelly wrote:
>> Or simply an explicit declaration of scope at the beginning of the
>> function definition.
>
> One of the reasons I switched to Python was to not have to do that, or
> hardly ever. For valid code, an new declaration is hardly needed. Parameters
> are locals. If the first use of another name binds it (and that includes
> import, class, and def), it is local. If the first use of does not bind it,
> it had better not be local (because if it is, there well be an exception).
> If there are branches, each should be consistent with the others. One should
> only need two readings to understand and fix unbound local errors.

In general I agree, although when reading code I would definitely
prefer if the locals were declared.

On a related note, I think that generator functions should in some way
be explicitly marked as such in the declaration, rather than needing
to scan the entire function body for a yield statement to determine
whether it's a generator or not.