Negative array indicies and slice()

[Steven D'Aprano]

On Mon, 29 Oct 2012 11:19:38 +0000, Steven D'Aprano wrote:

> Because xrange represents a concrete sequence of numbers, all three of
> start, end and stride must be concrete, known, integers:
> 
> py> xrange(4, None, 2)
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> TypeError: an integer is required
> 
> Whereas slices can trivially include blanks that get filled in only when
> actually used:
> 
> py> "hello world"[aslice]
> 'owrd'
> py> "NOBODY expects the Spanish Inquisition!"[aslice] 
> 'D xet h pns nusto!'

/me facepalms/


Argggh, I forgot to copy-and-paste the critical line defining aslice:

aslice = slice(4, None, 2)


Sorry about that.



-- 
Steven