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[Python-Dev] PEP 549: Instance Properties (aka: module properties)

Ethan Furman ethan at stoneleaf.us
Mon Sep 11 21:54:21 EDT 2017 
On 09/06/2017 08:26 AM, Guido van Rossum wrote:

> So we've seen a real use case for __class__ assignment: deprecating things on access. That use case could also be solved
> if modules natively supported defining __getattr__ (with the same "only used if attribute not found otherwise" semantics
> as it has on classes), but it couldn't be solved using @property (or at least it would be quite hacky).
>
> Is there a real use case for @property? Otherwise, if we're going to mess with module's getattro, it makes more sense to
> add __getattr__, which would have made Nathaniel's use case somewhat simpler. (Except for the __dir__ thing -- what else
> might we need?)

Doesn't assigning a module's __class__ make it so we can already write properties, descriptors, __getattr__, etc. ?  Are 
these other things so common that we need /more/ syntax for them?

--
~Ethan~
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