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

From	Chet Ramey <chet.ramey@case.edu>
Newsgroups	gnu.bash.bug
Subject	Re: Should [[ -v 1 ]] be supported?
Date	2018-12-28 18:23 -0600
Organization	ITS, Case Western Reserve University
Message-ID	<mailman.6487.1546043048.1284.bug-bash@gnu.org> (permalink)
References	(3 earlier) <CABrM6wkGwVbPdrXTetVsFCiwDPg5JnK4KRh49WqACsKhrrMMdA@mail.gmail.com> <20181228013623.mersdxbzy64dpldp@crack.deadbeast.net> <CABrM6w=2zrjmV24VAgzioAu2iNcyuf3tsi--cfvkCH6MJ7feRA@mail.gmail.com> <20181228015710.tzzbejk36fsgr5wb@crack.deadbeast.net> <CABrM6wkfvTzY5UBMDz_kNr=imV_KpSsFF6o8fV5RLrKMYrPKgg@mail.gmail.com>

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On 12/27/18 11:32 PM, Peng Yu wrote:
>> 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. 

This isn't a major deductive leap, since command substitution forks a
child and reads through a pipe. Forking is always more expensive than
not.

-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
		 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU    chet@case.edu    http://tiswww.cwru.edu/~chet/

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Re: Should [[ -v 1 ]] be supported? Chet Ramey <chet.ramey@case.edu> - 2018-12-28 18:23 -0600

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