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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Strongly disagree that
not ximplies to programmers thatxis a bool.well it does not imply directly per se since you can "not" many things but I feel like my first assumption would be it is used in a bool context
I would say it depends heavily on the language. In Python, it's very common that different objects have some kind of Boolean interpretation, so assuming that an object is a bool because it is used in a Boolean context is a bit silly.
if not x then … endis very common in Lua for similar purposes, very rarely do you see hard nil comparisons or calls totypeof(last time I did was for a serializer).