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Python Performance: Why 'if not list' is 2x Faster Than Using len() (blog.codingconfessions.com)
submitted 3 months ago by abhi9u@lemmy.world to c/technology@lemmy.world
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[-] knighthawk0811@lemmy.ml 7 points 3 months ago

so these are the only 2 ways then? huge if true

[-] sugar_in_your_tea@sh.itjust.works 1 points 3 months ago* (last edited 3 months ago)

Oh, there are plenty of other terrible ways:

for _ in mylist:
    break
else:
    # whatever you'd do if mylist was empty

if not any(True for _ in mylist):

try:
    def do_raise(): raise ValueError

    _ = [do_raise() for _ in mylist]
except ValueError:
    pass
else:
    # whatever you'd do i mylist was empty

I could probably come up with a few others as well.

Please note that none of these handles the TypeError if mylist is None.

this post was submitted on 12 Apr 2025
209 points (100.0% liked)

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