I agree.
What I meant is that it is unreliable with `v is 710` and even more unreliable
with `v == 710` as β==β is less strict than βisβ.
DG
> On 12 Sep 2023, at 21:03, Rob Cliffe <rob.cli...@btinternet.com> wrote:
>
>
>>> As for the example in your first post:
>>> var = 710
>>> variable_name = [k for k, v in locals().items() if v == 710][0]
>>> print("Your variable name is " + variable_name)
>>>
>>> it does "work", but it doesn't make much sense with Python's semantics.
>>> You could have two identifiers bound to the same object; which one you got
>>> hold of would be essentially random.
>> Yes, if `==` was replaced by `is`. Currently it is even more random as it
>> would return the first one which evaluates __eq__() positively.
>>
> I'm not sure what you're saying. In:
> var1 = 710
> var2 = 710
> variable_names = [k for k, v in locals().items() if v is 710]
> Depending on the Python implementation, variable_names may be ['var1',
> 'var2'] or it may be empty (depending on whether 710 is interned). It could
> also in theory contain one of 'var1', 'var2' but not the other, though I
> would be surprised if that happened in practice. The behaviour is not
> guaranteed and should not be relied on.
> Rob Cliffe
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