Tuple assignment and generators?

[Sion Arrowsmith]

vdrab <stijndesaeger at gmail.com> wrote:
>let's say there's a certain property P, for the sake of this loooong
>discussion, something
>more or less like a class or type's property of "having immutable
>values, such that any instance with value X has a single, unique
>representation in memory and any two instantiations of objects with
>that value X are in fact references to the same object".
>
>Then, for example, python strings have property P whereas python lists
>do not:

Er, no:

>>> x = "test!"
>>> y = "test!"
>>> x == y
True
>>> x is y
False

Strings only get a unique instance if they are valid identifiers.
Again, it's an optimisation issue. As with ints, it

>_depends_on_their_value_.

>I find it neither evident nor consistent. I don't think the above post
>explains this, regardless of how you read "implementation".

"Implementation dependent" => "Any behaviour you observe which is not
explicitly documented is not to be relied upon". Also, "Implementation
dependent" => "How this is implemented should be transparent and
irrelevant to the normal user". No, it's not particularly consistent.
Because it doesn't matter.

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