[Tutor] Why does CPython cache small integers "asymmetrically"?

[Alan Gauld]

On 27/05/2021 02:49, boB Stepp wrote:
> I often wonder how Python design decisions are reached.  I wish there
> was a single go-to place for these sorts of questions!
> 
Technically this is an implementation decision, I don;t think
the Python language requires small ints to be cached, its
a purely CPython design choice and could change.

> I cannot resist asking why -- if anyone happens to know -- more
> positive integers are cached than negative ones:

I'd guess because positive ints are used way more often than
negative ones. I very rarely use a negative number literal
or even perform operations where I expect to get a negative
result. Index searches and limits and slices etc are all
specified by positive numbers except for a very few
negatives used for accessing end points(-1 thru' -5 at most!)

-- 
Alan G
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