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Comment by frou_dh | Hacker News Reader

Notably, such a concept as a function having a local variable is beyond POSIX shell.

Indeed, and local is one of the few non-POSIX things that Debian people famously could not live without, and so is required to exist in all Debian shells that can be used as /bin/sh such as the Debian Almquist shell.

* https://debian.org/doc/debian-policy/ch-files.html#s-scripts

"Variables may be declared to be local to a function by using a 'local' command."

Here's the spec. Where is it? https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V...

It is in both ash and dash, the shells I mentioned. Your attempt at point scoring is irrelevant but expected.

ash & dash are about 100kB executables (POSIX plus a tiny number of non-interactive improvments like 'local'), bash is 1100kB. Every shell and subshell.

My point is that POSIX shell purity is masochism. Understanding how it's the core and other shells build on top of it is certainly valuable, but it's not inherently particularly good to use.

Maybe we are at cross purposes. My default shell is bash, but my default "sh" is dash. This is as it should be (and is default in Debian & Ubuntu I think).

If you are talking about interactive use, of course bash is the one to use, but for writing shell scripts, it is a 10X interactivity overhead" over dash.

IMO it's a big win for scripts to at least be able to use Arrays in that otherwise "stringly-typed" world.

As a POSIX shell masochist myself, Arrays are the single biggest missing feature. POSIX shells actually do have one array: $@. Having more would make my life so much easier.

The amount of gyrations I go through to account for the lack of arrays is easily 1000x worse than accounting for not having local variables.

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