[Python-ideas] Where did we go wrong with negative stride?

[Rob Cliffe]

> I wonder if it would have been simpler if we had defined a[i:j:-1] as 
> the reverse of a[i:j]?
>
Maybe, I'm not venturing an opinion.
But if so:  What about negative strides other than -1?  Should a[i:j:-2] 
always be the reverse of a[i:j:2]?
My feeling is not, i.e.
"abcdefghij"[3:8:2] == "dfh"
but I feel that
"abcdefghij"[3:8:-2] under this suggestion should be what 
"abcdefghij"[8:3:-2] is now, i.e. "ige", not "hfd".
I.e. any non-empty start:stop:stride slice where 0 <= slice < length 
should always start with the character indexed by "start".
Rob Cliffe
> What are real use cases for negative strides?
>
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