04.07.18 05:42, Steven D'Aprano пише:
On Tue, Jul 03, 2018 at 09:54:22PM -0400, Terry Reedy wrote:
results = [(x, y, x/y) for x in input_data for y in [f(x)] if y > 0]
Would (f(x),) be faster?
There is a deferred feature request to optimize "for x in [item]" as
equivalent to "for x in (item,)", to avoid constructing a list:
https://bugs.python.org/issue32856
No, this optimization was already made in issue32925. Issue32856 is a
different optimization -- it makes such constructions be as fast as a
simple assignment. It allows to use an assignment in comprehensions
without introducing a new syntax and with zero overhead.
_______________________________________________
Python-Dev mailing list
Python-Dev@python.org
https://mail.python.org/mailman/listinfo/python-dev
Unsubscribe:
https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com