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

Baptiste Carvello devel at baptiste-carvello.net
Thu Jun 28 08:05:26 EDT 2018

Le 28/06/2018 à 01:31, Greg Ewing a écrit :
> Well, I remain profoundly unconvinced that writing comprehensions
> with side effects is ever a good idea, and Tim's examples did
> nothing to change that.

Comprehensions with side effects feel scary indeed. But I could see
myself using some variant of the "cumsum" example (for scientific work
at the command prompt):

>>> x=0; [x:=x+i for i in range(5)]

Here the side effects are irrelevant, the "x" variable won't be reused.
But it needs to be initialized at the start of the comprehension.

I would happily get rid of the side-effects, but then what would be a
non-cryptic alternative to the above example?


More information about the Python-Dev mailing list