Why does setdefault evaluate default when key is set?
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Chapters
00:00 Why Does Setdefault Evaluate Default When Key Is Set?
00:29 Accepted Answer Score 10
00:55 Thank you
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Full question
https://stackoverflow.com/questions/2279...
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https://meta.stackexchange.com/help/lice...
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Tags
#python #setdefault
#avk47
Rise to the top 3% as a developer or hire one of them at Toptal: https://topt.al/25cXVn
--------------------------------------------------
Music by Eric Matyas
https://www.soundimage.org
Track title: Sunrise at the Stream
--
Chapters
00:00 Why Does Setdefault Evaluate Default When Key Is Set?
00:29 Accepted Answer Score 10
00:55 Thank you
--
Full question
https://stackoverflow.com/questions/2279...
--
Content licensed under CC BY-SA
https://meta.stackexchange.com/help/lice...
--
Tags
#python #setdefault
#avk47
ACCEPTED ANSWER
Score 10
The problem is not in setdefault, but in a general principle in Python (as well as most languages) that all arguments must be evaluated before the function is called. That is, even before Python checks to see if the key is in the dictionary, it needs to know the value of both the key and the default value: and since the default value is the result of a function, that function must be called first.