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Date: Wed, 15 Jul 2015 13:04:32 +0200
From: Antoon Pardon <antoon.pardon@rece.vub.ac.be>
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Subject: Re: Possibly Pythonic Tail Call Optimization (TCO/TRE)
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Xref: csiph.com comp.lang.python:93864

On 07/15/2015 12:55 PM, Marko Rauhamaa wrote:
> Ned Batchelder <ned@nedbatchelder.com>:
>
>> On Wednesday, July 15, 2015 at 2:44:55 AM UTC-4, Marko Rauhamaa wrote:
>>> The other problem for tail call elimination is the requirement that
>>> functions return None by default. Smooth tail call elimination would
>>> require that Python leave the default return value unspecified.
>> I don't understand this, can you explain more? Are you saying that the
>> Python specification shouldn't specify what x becomes?:
>>
>>     def who_knows():
>>         pass
>>
>>     x = who_knows()
> Yes, that's what I'm saying. The implementation would be free to assign
> any value whatsoever to x.

And can you explain why this would be needed foor smooth tail call elimination?

-- 
Antoon Pardon.