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From: Chris Down <chris@chrisdown.name>
Newsgroups: gnu.bash.bug
Subject: Re: performance bug of [[ $x ]]
Date: Sun, 8 Mar 2020 02:10:11 +0000
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Peng Yu writes:
>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?

Like I said, `perf` is perfectly adequate.

     bash -c 'x=$(printf "%.sx" {1..10000000}); perf record -g -p $$ & sleep 2; time [[ $x ]]'

You might as well just use `:`.