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Date: Tue, 14 Jul 2015 23:43:22 +1000
Subject: Re: Possibly Pythonic Tail Call Optimization (TCO/TRE)
From: Chris Angelico <rosuav@gmail.com>
Cc: "python-list@python.org" <python-list@python.org>
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On Tue, Jul 14, 2015 at 11:38 PM, Marko Rauhamaa <marko@pacujo.net> wrote:
> Chris Angelico <rosuav@gmail.com>:
>
>> On Tue, Jul 14, 2015 at 10:28 PM, Marko Rauhamaa <marko@pacujo.net> wrote:
>>> I would rather optimize by default and disable optimizations with
>>> --debug or equivalent.
>>
>> That assumes that it's simply an optimization. This is a distinct
>> semantic change.
>
> No, tail call optimization doesn't change the behavior of the program,
> for the worse anyway.

It does, because you lose traceback records. That's pretty significant
when you come to try to debug something.

ChrisA