197
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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Yea and then you use "not" with a variable name that does not make it obvious that it is a list and another person who reads the code thinks it is a bool. Hell a couple of months later you yourself wont even understand that it is a list. Moreover "not" will not throw an error if you don't use an sequence/collection there as you should but len will.
You should not sacrifice code readability and safety for over optimization, this is phyton after all I don't think list lengths will be your bottle neck.
Strongly disagree that
not ximplies to programmers thatxis a bool.i haven’t programmed since college 15 years ago and even i know that 0 == false for non bool variables. what kind of professional programmers wouldn’t know that?