[Haskell-beginners] splitAt and negative values

[Tom Murphy]

One problem you might run into is:

a = 4
b = 5
splitAt (a - b) [1..]

If you don't know what a or b are beforehand, you might be opening up a can
of uncomputable worms.

Tom
On Sep 6, 2012 1:25 PM, "Stayvoid" <stayvoid at gmail.com> wrote:

> Hello,
>
> Could you explain this behaviour?
>
> > splitAt (-1) "Foobar"
> ("","Foobar")
> > splitAt (-100) "Foobar"
> ("","Foobar")
>
> I don't understand why splitAt (-1) "Foobar" doesn't output this:
> ("r", "Fooba")
> or this:
> ("", "Fooba")
>
> How does it work?
>
> Python's list slicing looks similar, but results for negative values
> differ:
> >>> a = "Foobar"
> >>> a[:-1]
> >>> 'Fooba'
>
> Thanks
>
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