[Python-Dev] (name := expression) doesn't fit the narrative of PEP 20

Tim Peters tim.peters at gmail.com
Fri Apr 27 17:11:31 EDT 2018


[Chris Angelico <rosuav at gmail.com>]
> ...
> I don't understand why people bring up all these arguments that have
> absolutely nothing to do with the proposal at hand. None of this has
> in any way changed.

That's easy:  any time there's a long thread to which Guido has
contributed at least twice, it will be seen as a Golden Opportunity to
re-litigate every decision that's ever been made ;-)

Some amount of that seems healthy to me (people are thinking about
"language design" from a larger view than the proposal du jour).  In
this specific case, line-oriented coverage tools have missed
accounting for all possible code paths since day #1; e.g.,

    x = f() or g()

You don't need to reply to messages so obviously irrelevant to the PEP
unless you want to.  It's not like Guido will read them and go "oh!  a
binding expression in a ternary conditional is a fundamentally new
potential problem for a line-oriented coverage tool!  that's fatal"
;-)


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