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Re: Optimisation request

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From Chet Ramey <chet.ramey@case.edu>
Newsgroups gnu.bash.bug
Subject Re: Optimisation request
Date Thu, 29 Nov 2018 09:02:28 -0800
Organization ITS, Case Western Reserve University
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On 11/26/18 1:29 PM, Martijn Dekker wrote:
> I've noticed bash-5.0beta is quite a bit faster than bash-4.4 in running a
> lot of pure shell code. Good news.
> 
> One optimisation that isn't done yet: if a subshell function like
> 
>     f() (foo)
> 
> is used in a command substitution, it forks twice. I would like it if it
> could be optimised to eliminate the fork if the subshell function is the
> last command in the command substitution.

There is already code to optimize subshell commands like this; it's just
disabled until bash-5.1 so I have more time to test it.

Chet

-- 
``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: Optimisation request Chet Ramey <chet.ramey@case.edu> - 2018-11-29 09:02 -0800

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