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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Isn't it because list is linked list, so to get the Len it has to iterate over the whole list whereas to get emptyness it just have to check if there is a 1st element ?
I' too lazy to read the article BTW.
So… it has to iterate over the whole empty list is what you’re saying? like once for every of the zero items in the list?
The list is not necessarily empty. If you were sure it was, why check?