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From: Martijn Dekker <martijn@inlv.org>
Newsgroups: gnu.bash.bug
Subject: Optimisation request
Date: Mon, 26 Nov 2018 22:29:39 +0100
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Xref: csiph.com gnu.bash.bug:14855

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.

Thanks,

- M.