Re: question about parameter expansion

[ZyX <kp-pav@xxxxxxxxx>]

26.09.2015, 16:38, "Mikael Magnusson" <mikachu@xxxxxxxxx>:
> On Sat, Sep 26, 2015 at 12:18 PM, Dmitri Vereshchagin
> <dmitri.vereshchagin@xxxxxxxxx> wrote:
>>  Hello.
>>
>>  Here is a code sample I would like to rewrite using parameter expansion
>>
>>    if (( ${+foo} )); then
>>      bar=
>>    else
>>      bar=baz
>>    fi
>>
>>  Cannot find it in the docs, but I suppose there is a way to do that. Am
>>  I right?
>>
>>  Thanks.
>>
>>  --
>>  Dmitri Vereshchagin
>
> You have to think outside the box for this one,
> bar=${${${+foo}#1}//0/baz}

Why not simply

    bar=${foo+baz}

?

>
> --
> Mikael Magnusson