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| From | Chet Ramey <chet.ramey@case.edu> |
| Newsgroups | gnu.bash.bug |
| Subject | Re: Error on arithmetic evaluation of `~0`. |
| Date | Sat, 29 Dec 2018 10:46:18 -0600 |
| Organization | ITS, Case Western Reserve University |
| Lines | 34 |
| Approved | bug-bash@gnu.org |
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| To | Bize Ma <binaryzebra@gmail.com> |
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On 12/28/18 11:26 PM, Bize Ma wrote:
> Chet Ramey (<chet.ramey@case.edu <mailto:chet.ramey@case.edu>>) wrote:
>
> On 12/23/18 12:01 PM, Bize Ma wrote:
>
> {…}
>
> > Both command line above should have printed "hello".
>
> No. 0 is the only valid subscript for a non-array variable. The difference
> between bash and other shells that implement this feature is that bash
> warns about negative subscripts.
>
>
> If you say so: fine for me.
>
> It still irks me a little that a `${var[-1]}` isn't the "last value"
> (sometimes!, consistency?).
The goal is not to make non-array variables look exactly like array
variables; the goal is to provide a little bit of syntactic sugar in
the rare case that it's useful. It's the analog to referencing an array
variable without using a subscript, which references element 0.
> I haven't seen that documented anywhere, though.
Which part? The fact that non-array variables can be referenced using
subscript 0?
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU chet@case.edu http://tiswww.cwru.edu/~chet/
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Re: Error on arithmetic evaluation of `~0`. Chet Ramey <chet.ramey@case.edu> - 2018-12-29 10:46 -0600
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