Re: Should [[ -v 1 ]] be supported?

From	Peng Yu <pengyu.ut@gmail.com>
Newsgroups	gnu.bash.bug
Subject	Re: Should [[ -v 1 ]] be supported?
Date	2018-12-27 23:32 -0600
Message-ID	<mailman.6441.1545975916.1284.bug-bash@gnu.org> (permalink)
References	(2 earlier) <abd86dbc-f6e2-62bd-e9dc-f959e2dbff9f@inlv.org> <CABrM6wkGwVbPdrXTetVsFCiwDPg5JnK4KRh49WqACsKhrrMMdA@mail.gmail.com> <20181228013623.mersdxbzy64dpldp@crack.deadbeast.net> <CABrM6w=2zrjmV24VAgzioAu2iNcyuf3tsi--cfvkCH6MJ7feRA@mail.gmail.com> <20181228015710.tzzbejk36fsgr5wb@crack.deadbeast.net>

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> You're whacking moles.  Use a profiler.  That's what they're for.

I've already shown that $() is a major problem to slow down the speed
and I have reduced using its usage in my code and significantly
improved the performance. Nevertheless, it doesn't mean that it is not
necessary to systematically evaluating features that are used
frequently.

> Yes, I can.  You need to identify where bash is _actually_ spending most
> of its execution time, and a profiler can help you do that.

Yes and no. For a particular bash script, you can quantify which bash
features are the most time-consuming. But you can not profile all the
bash scripts that have ever been written. Since there are only limited
features in bash, in this case, a logical way to go is to at least
profile each commonly used feature with minimal code (as just for and
repetitive calling that features as I do) and understand its pros and
cons. A profiler is an overkill in this case.

-- 
Regards,
Peng

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Re: Should [[ -v 1 ]] be supported? Peng Yu <pengyu.ut@gmail.com> - 2018-12-27 23:32 -0600

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