195
Python Performance: Why 'if not list' is 2x Faster Than Using len()
(blog.codingconfessions.com)
this post was submitted on 12 Apr 2025
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But the first example does the same thing for an empty list. I guess the lesson is that if you’re measuring the speed of arbitrary stylistic syntax choices, maybe Python isn’t the best language for you.
Yes, the first example does the same thing, but there's still less to mentally parse. Ideally you should just use
if len(mylist) == 0:.