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From: Peng Yu <pengyu.ut@gmail.com>
Newsgroups: gnu.bash.bug
Subject: Re: performance bug of [[ $x ]]
Date: Sat, 7 Mar 2020 18:33:19 -0600
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Xref: csiph.com gnu.bash.bug:16000

Could you show me how you do the profiling for this specific case?
Based on what proof that you can conclude that it is not the `[[`
performance problem?

On 3/7/20, Chris Down <chris@chrisdown.name> wrote:
> Peng Yu writes:
>>[[ $x ]] just tests whether the variable $x is of length 0 or not. So
>>its performance should not depend on how long the variable is.
>
> Who said it has anything to do with the [[ builtin's performance? A shell
> does
> a lot more than just running one command.
>
> For this and the last issue you posted, you could quite trivially find out
> the
> answer yourself using `perf` or another profiler.
>


-- 
Regards,
Peng