why does dead code costs time?
tjreedy at udel.edu
Wed Dec 5 21:41:19 CET 2012
On 12/5/2012 1:24 PM, Bruno Dupuis wrote:
> On Wed, Dec 05, 2012 at 10:59:26AM -0700, Ian Kelly wrote:
>> On Wed, Dec 5, 2012 at 10:34 AM, Steven D'Aprano
>> <steve+comp.lang.python at pearwood.info> wrote:
>>> The difference is almost certain between the LOAD_CONST and the
>>> As to *why* there is such a difference, I believe that's a leftover from
>>> early Python days when None was not a keyword and could be reassigned.
>> I think this should even be considered a bug, not just a missing
>> optimization. Consider:
> This is definitely a bug
>>>>> globals()['None'] = 42
>>>>> def f(x):
>> ... return None
>> ... print(x)
> This one is pretty scary
> The difference between `return None` and `return` leads to inconsistency and
> is in contradiction with the specs, AFAIK. I'm glad we pointed this out.
You did not specify version, but I confirmed in 3.3.0. Please open a
Terry Jan Reedy
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