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Re: How to test if a variable exists and is a hash?
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From: |
Lawrence Velázquez |
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Subject: |
Re: How to test if a variable exists and is a hash? |
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Date: |
Sat, 11 Jul 2020 18:49:13 -0400 |
> On Jul 11, 2020, at 6:33 PM, Peng Yu <pengyu.ut@gmail.com> wrote:
>
> On 7/11/20, Koichi Murase <myoga.murase@gmail.com> wrote:
>> 2020-07-12 0:43 Peng Yu <pengyu.ut@gmail.com>:
>>> What is the best way to check if a variable exists and is a hash? Thanks.
>>
>> Why don't you use '${x@a}'?
>>
>> $ declare -A x=()
>> $ [[ ${x@a} == *A* ]]
>
> I am not familar with the usage of ${x@a}. Where is it documented? Thanks.
In both the man page and the manual.
https://www.gnu.org/software/bash/manual/html_node/Shell-Parameter-Expansion.html
vq