[Python-Dev] Informal educator feedback on PEP 572 (was Re: 2018 Python Language Summit coverage, last part)

[Antoine Pitrou]

Why is this discussion talking about comprehensions at all?
Is there a decent use case for using assignments in comprehensions (as
opposed to language lawyering or deliberate obfuscation)?

Regards

Antoine.


On Thu, 28 Jun 2018 01:25:14 +1200
Greg Ewing <greg.ewing at canterbury.ac.nz> wrote:
> Ivan Pozdeev via Python-Dev wrote:
> > Using this assigned result elsewhere in the same expression (akin to 
> > regex backreferences) is not a part of the basic idea actually.  
> 
> If that's true, then the proposal has mutated into something
> that has *no* overlap whatsoever with the use case that started
> this whole discussion, which was about binding a temporary
> variable in a comprehension, for use *within* the comprehension.
> 
> > It depends on the evaluation order (and whether something is evaluated 
> > at all),  
> 
> Which to my mind is yet another reason not to like ":=".
>