[Python-ideas] [Python-Dev] What's the status of PEP 505: None-aware operators?

Steven D'Aprano steve at pearwood.info
Wed Nov 29 17:52:02 EST 2017

On Wed, Nov 29, 2017 at 06:49:14AM -0800, David Mertz wrote:
> I didn't say no use case exists, but rather "too special case." And/or
> shortcutting is great, but truthiness feels much more general than noneness
> to me.

Of course truthiness is much more general than Noneness -- and that's 
precisely the problem with using `or`. It's too general.

If you haven't read the PEP, you should, because this is extensively 
discussed there. One of the problems the author discusses is that `or` 
is recommended on Stackoverflow as the best way to perform short-cutting 
None tests, often with no caveats given.

We've been here before. Python old-timers may remember the former 
idiomatic way to get a ternary if expression:

    condition and first or second

which was also buggy (if first happens to be falsey, second is returned 
even when condition is true).


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