[Python-ideas] PEP 562

[Michel Desmoulin]

If I recall there was a proposal a few months for a "lazy" keyword that
would render anything lazy, including imports.

Instead of just adding laziness on generators, the  on imports, then who
knows where, maybe it's time to consider laziness is a hell of a good
general concept and try to generalize it ?

For imports, that would mean:

lazy from module import stuff
lazy import foo

For the rest,

bar = lazy 1 + 1

When you think about it, it's syntaxic sugar to avoid manually wrapping
everything in functions, storying stuff in closure and calling that later.

Le 12/09/2017 à 10:26, Ivan Levkivskyi a écrit :
> @Anthony
>> module.__getattr__ works pretty well for normal access, after being
>> imported by another module, but it doesn't properly trigger loading by
>> functions defined in the module's own namespace.
> 
> The idea of my PEP is to be very simple (both semantically and in terms
> of implementation). This is why I don't want to add any complex logic.
> People who will want to use __getattr__ for lazy loading still can do this
> by importing submodules.
> 
> @Nathaniel @INADA
>> The main two use cases I know of for this and PEP 549 are lazy imports
>> of submodules, and deprecating attributes.
> 
> Yes, lazy loading seems to be a popular idea :-)
> I will add the simple recipe by Inada to the PEP since it will already work.
> 
> @Cody
>> I still think the better way
>> to solve the custom dir()  would be to change the module __dir__
>> method to check if __all__ is defined and use it to generate the
>> result if it exists. This seems like a logical enhancement to me,
>> and I'm planning on writing a patch to implement this. Whether it
>> would be accepted is still an open issue though.
> 
> This seems a reasonable rule to me, I can also make this patch if
> you will not have time.
> 
> @Guido
> What do you think about the above idea?
> 
> --
> Ivan
> 
> 
> 
> 
> _______________________________________________
> Python-ideas mailing list
> Python-ideas at python.org
> https://mail.python.org/mailman/listinfo/python-ideas
> Code of Conduct: http://python.org/psf/codeofconduct/
>