Optimisation request

[Martijn Dekker]

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.

[Chet Ramey]

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